Monday, April 20, 2009

14k White Gold Diamond Set Engagement Ring Jewelry

500 carat flawless diamond found

NATURE | Diamonds | The Pinks of Argyle

Diamond and Gold

Blue Diamond

The Unique Properties of Diamonds


The diamond is the best known and the most heavily marketed gemstone. Like graphite, lonsdaleite ("hexagonal diamond"), and the fullerenes, a diamond is an allotrope of carbon and, no matter what its size, each diamond can be considered to be a single molecule of carbon.

Diamond is the hardest natural substance (while carbon is one of the softest). The word diamond derives from Greek adamas or "hardest steel". Pliny the Elder (A.D. 23 to 79) wrote that "the best way to test adamas is upon the anvil; strike even upon the point of the adamas with a hammer as hard as you can, it defies all blows and instead of the stone yielding, the hammer flies into pieces and even the anvil splits in half." This experiment, however, is not recommended: though hard, a diamond is brittle, and can crack under the shock of a sudden, sharp blow.

Diamond has an isometric crystallography. The crystal structure of a diamond, called a face centered cubic lattice, derives from the way each carbon atom joins four other carbon atoms in regular tetrahedrons (triangular prisms). It is possible to cleave, or split, a diamond, along its crystal face (grain), such that each side of the cleavage remains smooth.

The adamantine luster (the brilliance and "fire") of a diamond is due to its high dispersion and its high refractive index (a measure of how far it can bend light). Commercial gem diamonds are colorless or pale, steely blue. Strongly colored gem diamonds, called "fancies," are extremely rare and valuable (especially red, pink, and blue). Diamonds can also be gray, yellow, brown, green, orange, lavender, and even black. Diamond crystals frequently contain inclusions of other minerals. Many diamonds fluoresce blue to violet and the effect is sometimes strong enough to be seen in daylight. Some blue-fluorescing diamonds phosphoresce yellow (afterglow reaction).

Diamond has a high specific gravity. A diamond does not conduct electricity well (it is a semiconductor), but conducts heat extremely well. At a high enough temperature in the presence of oxygen, diamond can burn.

Composition and color

Diamonds occur in a restricted variety of colors — black, brown, yellow, gray, white, blue, orange, purple to pink, red, and chartreuse. Colored diamonds contain crystallographic defects, including substitutional impurities and structural defects, that cause the coloration. Theoretically, pure diamonds would be transparent and colorless. Diamonds are scientifically classed into two main types and several subtypes, according to the nature of defects present and how they affect light absorption:

Type I diamond has nitrogen (N) atoms as the main impurity, at a concentration of up to 1 percent. If the N atoms are in pairs they do not affect the diamond's color; these are Type IaA. If the N atoms are in larger aggregates they impart a yellow to brown tint (Type IaB); the yellow color mostly originates from 3-nitrogen complexes (N3 center). About 98 percent of gem diamonds are type Ia, and most of these are a mixture of IaA and IaB material: these diamonds belong to the Cape series, named after the diamond-rich region formerly known as Cape Province in South Africa, whose deposits are largely Type Ia. If the N atoms are dispersed throughout the crystal in isolated sites (not paired or grouped), they give the stone an intense yellow or occasionally brown tint (Type Ib); the rare canary diamonds belong to this type, which represents only one per thousand of known natural diamonds. Synthetic diamond containing nitrogen is usually type Ib. Type I diamonds absorb in both the infrared and ultraviolet region, from 320 nm. They also have a characteristic fluorescence and visible absorption spectrum (see Optical properties).

Type II diamonds have very few if any nitrogen impurities. Type IIa diamond can be colored pink, red, or brown due to structural anomalies arising through plastic deformation during crystal growth[21] — these diamonds are rare (1.8 percent of gem diamonds), but constitute a large percentage of Australian production. Type IIb diamonds, which account for 0.1 percent of gem diamonds, are usually a steely blue or gray due to scattered boron within the crystal matrix; these diamonds are also semiconductors, unlike other diamond types (see Electrical properties). Most blue-gray diamonds coming from the Argyle mine of Australia are not of type IIb, but of Ia type. Those diamonds contain large concentrations of defects and impurities (especially hydrogen and nitrogen) and the origin of their color is yet uncertain[11]. Type II diamonds absorb in a different region of the infrared (which absorption is due to the diamond lattice rather than impurities), and transmit in the ultraviolet below 225 nm, unlike type I diamonds. They also have differing fluorescence characteristics, but no discernible visible absorption spectrum.

Certain diamond enhancement techniques are commonly used to artificially produce an array of colors, including blue, green, yellow, red, and black. Color enhancement techniques usually involve irradiation, including proton and deuteron bombardment via cyclotrons; neutron bombardment via the piles of nuclear reactors; and electron bombardment via Van de Graaff generators. These high-energy particles physically alter the diamond's crystal lattice, knocking carbon atoms out of place and producing color centers. The depth of color penetration depends on the technique and its duration, and in some cases the diamond may be left radioactive to some degree.

It should be noted that some irradiated diamonds are completely natural—one famous example is the Dresden Green Diamond. In these natural stones the color is imparted by "radiation burns" (natural irradiation by alpha particles originating from uranium ore) in the form of small patches, usually only skin deep. Additionally, Type IIa diamonds can have their structural deformations "repaired" via a high-pressure high-temperature (HPHT) process, removing much or all of the diamond's color.

Thermal stability

Being a form of carbon, diamond graphitizes in the presence of oxygen if heated over 800 °C (1500 °F). In absence of oxygen, e.g. in a flow of high-purity Ar gas, diamond can be heated up to ~1700 °C[18][19]. Its surface blackens, but can be recovered by re-polishing. At high pressure (~20 GPa) diamond can be heated up to 2500 °C[20] and recent unpublished reports reveal that diamond can withstand ~3000 °C.

In the late 18th century, diamonds were demonstrated to be made of carbon by the rather expensive experiment of igniting a diamond (by means of a burning-glass) in an oxygen atmosphere and showing that carbonic acid gas (carbon dioxide) was the product of the combustion. The fact that diamonds are combustible bears further examination because it is related to an interesting fact about diamonds. Diamonds are carbon crystals that form deep within the Earth under high temperatures and extreme pressures. At surface air pressure (one atmosphere), diamonds are not as stable as graphite, and so the decay of diamond is thermodynamically favorable (δH = −2 kJ / mol). Diamonds had previously been shown to burn during Roman times.

So, despite De Beers' 1948 ad campaign, diamonds are definitely not forever. However, owing to a very large kinetic energy barrier, diamonds are metastable; they will not decay into graphite under normal conditions.[citation needed

Thermal conductivity

Unlike most electrical insulators, diamond is a good conductor of heat because of the strong covalent bonding within the crystal. Most natural blue diamonds contain boron atoms which replace carbon atoms in the crystal matrix, and also have high thermal conductance. Monocrystalline synthetic diamond enriched in 12C isotope (99.9%) has the highest thermal conductivity of any known solid at room temperature: >30 W/cm·K [16] five times more than copper. Because diamond has such high thermal conductance it is already used in semiconductor manufacture to prevent silicon and other semiconducting materials from overheating. At lower temperatures conductivity becomes even better as its Fermi electrons can match the phononic normal transport mode near the Debye point,[17] and transport heat more swiftly, to reach ~800 W/cm·K at 100 K (12C enriched diamond)[16]

Diamond's thermal conductivity is made use of by jewelers and gemologists who may employ an electronic thermal probe to separate diamonds from their imitations. These probes consist of a pair of battery-powered thermistors mounted in a fine copper tip. One thermistor functions as a heating device while the other measures the temperature of the copper tip: if the stone being tested is a diamond, it will conduct the tip's thermal energy rapidly enough to produce a measurable temperature drop. This test takes about 2–3 seconds. However, older probes will be fooled by moissanite, a crystalline mineral form of silicon carbide introduced in 1998 as an alternative to diamonds, which has a similar thermal conductivity.

Electrical properties

Except for most natural blue diamonds—which are semiconductors due to substitutional boron impurities replacing carbon atoms—diamond is a good electrical insulator. Natural blue or blue-gray diamonds, common for the Argyle diamond mine in Australia, are rich in hydrogen; these diamonds are not semiconductors and it is unclear whether hydrogen is actually responsible for their blue-gray color.[11] Natural blue diamonds containing boron and synthetic diamonds doped with boron are p-type semiconductors. N-type diamond films are reproducibly synthesized by phosphorus doping during chemical vapor deposition. Diode p-n junctions and UV light emitting diodes (LEDs, at 235 nm) has been produced by sequential deposition of p-type (boron-doped) and n-type (phosphorus-doped) layers.[12]
Main article: covalent superconductors

In April 2004 Nature reported that below the superconducting transition temperature 4 K, boron-doped diamond synthesized at high temperature and high pressure is a bulk, type-II superconductor[13]. Superconductivity was later observed in heavily boron-doped films grown by various chemical vapor deposition techniques, and the highest reported transition temperature (by 2009) is 11.4 K [14][15].

Optical properties

The luster of a diamond is described as 'adamantine', which simply means diamond-like. It is the highest luster possible bar that of metal (metallic), and is due to diamond's superlative hardness. Reflections on a properly cut diamond's facets are undistorted, due to their flatness. The refractive index of diamond (as measured via sodium light, 589.3 nm) is 2.417; because it is cubic in structure, diamond is also isotropic. Its high dispersion of 0.044 (B-G interval) manifests in the perceptible fire of cut diamonds. This fire—flashes of prismatic colors seen in transparent stones—is perhaps diamond's most important optical property from a jewelry perspective. The prominence or amount of fire seen in a stone is heavily influenced by the choice of diamond cut and its associated proportions (particularly crown height), although the body color of fancy diamonds may hide their fire to some degree.

Note that many other minerals have higher dispersion than diamond: sphene 0.051, andradite 0.057, cassiterite 0.071, SrTiO3 0.109, sphalerite 0.156, synthetic rutile 0.330 ![5] However the combination of dispersion with extreme hardness, wear and chemical resistivity, as well as clever marketing, determines the exceptional value of diamond as a gemstone.

Diamonds exhibit fluorescence of various colors and intensities under long wave (LW) ultra-violet light (365 nm): Cape series stones (type Ia; see composition and color) usually fluoresce blue, and these stones may also phosphoresce yellow. (This is a unique property among gemstones). Other LW fluorescence colors possible are green (usually in brown stones), yellow, mauve, or red (type IIb) [6]. In natural diamonds there is typically little if any response to shortwave (SW) ultraviolet, but the reverse is true of synthetics. Some natural type IIb diamonds phosphoresce blue after exposure to SW ultraviolet. In naturals, fluorescence under X-rays is generally bluish-white, yellowish or greenish. Some diamonds, particularly Canadian diamonds, show no fluorescence.

The origin of those luminescence colors is often unclear and not unique. Blue emission from type IIa and IIb diamonds is reliably identified with dislocations by directly correlating the emission with dislocations in an electron microscope.[7] However, blue emission in type Ia diamond could be either due to dislocations or the N3 defects (three nitrogen atoms bordering a vacancy)[8]. Green emission in type Ia diamond is usually due to the H3 center (two substitutional nitrogen atoms separated by a vacancy)[9]. Orange or red emission could be due to various reasons, one being the nitrogen-vacancy center which is present in sufficient quantities in all types of diamond, even type IIb.

Cape series diamonds have a visible absorption spectrum (as seen through a direct-vision spectroscope) consisting of a fine line in the violet at 415.5 nm—however, this line is often invisible until the diamond has been cooled to very low temperatures. Associated with this are weaker lines at 478 nm (often only this line is visible), 465 nm, 452 nm, 435 nm, and 423 nm. All those lines are labeled as N3 and N2 optical centers and associated with a defect consisting of three nitrogen atoms bordering a vacancy. Other stones show additional bands: brown, green, or yellow diamonds show a band in the green at 504 nm (H3 center, see above), sometimes accompanied by two additional weak bands at 537 nm and 495 nm (H4 center, a large complex presumably involving 4 substitutional nitrogen atoms and 2 lattice vacancies[10]). Type IIb diamonds may absorb in the far red due to the substitutional boron, but otherwise show no observable visible absorption spectrum.

Gemological laboratories make use of spectrophotometer machines that can distinguish natural, artificial, and color-enhanced diamonds. The spectrophotometers analyze the infrared, visible, and ultraviolet absorption and luminescence spectra of diamonds cooled with liquid nitrogen to detect tell-tale absorption lines that are not normally discernible.

Toughness

Unlike hardness, which only denotes resistance to scratching, diamond's toughness or tenacity is only fair to good. Toughness relates to the ability to resist breakage from falls or impacts: due to diamond's perfect and easy cleavage, it is vulnerable to breakage. A diamond will shatter if hit with an ordinary hammer.

Ballas and carbonado diamond are exceptional, as they are polycrystalline and therefore much tougher than single-crystal diamond; they are used for deep-drilling bits and other demanding industrial applications. Particular cuts of diamonds are more prone to breakage—such as marquis or other cuts featuring tapered points—and thus may be uninsurable by reputable insurance companies. The culet is a facet (parallel to the table) given to the pavilion of cut diamonds designed specifically to reduce the likelihood of breakage or splintering. Extremely thin, or very thin girdles are also prone to much higher breakage.

Solid foreign crystals are commonly present in diamond—these and other inclusions, such as internal fractures or "feathers"—can compromise the structural integrity of a diamond. Cut diamonds that have been enhanced to improve their clarity via glass infilling of fractures or cavities are especially fragile, as the glass will not stand up to ultrasonic cleaning or the rigors of the jeweler's torch. Fracture-filled diamonds may shatter if treated improperly.

Hardness and crystal structure


Known to the ancient Greeks as adamas ("tame'sles" or "bridleless") and sometimes called adamant, diamond is the hardest known naturally occurring material, scoring 10 on the old Mohs scale of mineral hardness. The material boron nitride, when in a form structurally identical to diamond (zincblende structure), is nearly as hard as diamond; a currently hypothetical material, beta carbon nitride, may also be as hard or harder in one form. Furthermore, it has been shown[2][3] that nanocrystalline diamond powder (sometimes called aggregated diamond nanorods) is tougher than diamond, i.e. performs better as abrasive material. In turn, using those new ultrahard materials for diamond testing, more accurate values are now known for diamond hardness. A (111) surface (normal to the largest diagonal of a cube) of type IIa diamond has a hardness value of 167 GPa (±6) when scratched with an nanodiamond tip, while the nanodiamond sample itself has a value of 310 GPa when tested with a nanodiamond tip [2]. However, the test only works properly with a tip made of harder material than the sample being tested. This means that the true value for nanodiamond is likely somewhat lower than 310 GPa.

Cubic diamonds have a perfect and easy octahedral cleavage, which means that they have four planes—directions following the faces of the octahedron where there are fewer bonds and therefore points of structural weakness—along which diamond can easily split (following a blunt impact), leaving smooth surfaces. Similarly, diamond's hardness is markedly directional: the hardest direction is the diagonal on the cube face, 100 times harder than the softest direction, which is the dodecahedral plane. The octahedral plane, followed by the axial directions on the cube plane, are intermediate between the two extremes. The diamond cutting process relies heavily on this directional hardness, as without it a diamond would be nearly impossible to fashion. Cleavage also plays a helpful role, especially in large stones where the cutter wishes to remove flawed material or to produce more than one stone from the same piece of rough.

Diamonds crystallize in the diamond cubic crystal system (space group Fd\bar{3}m) and consist of tetrahedrally, covalently bonded carbon atoms. A second form called lonsdaleite with hexagonal symmetry is also found, but it is extremely rare and forms in meteorites or in laboratory synthesis. The local environment of each atom is identical in the two structures. In terms of crystal habit, diamonds occur most often as euhedral (well-formed) or rounded octahedra and twinned, flattened octahedra known as macles (with a triangular outline). Other forms include dodecahedra and (rarely) cubes. There is some evidence that nitrogen impurities play an important role in the formation of euhedral crystals—the largest diamonds found, such as the Cullinan Diamond, have been shapeless or massive. These diamonds are type II and therefore contain little if any nitrogen (see Composition and color).
Diamond and graphite are two allotropes of carbon: pure forms of the same element that differ in structure.

The faces of diamond octahedrons are highly lustrous due to their hardness; growth defects in the form of trigons or etch pits are often present on the faces, the former being triangular pits whose points are aligned with the faces of the octahedron. A diamond's fracture may be step-like, conchoidal (shell-like, similar to glass) or irregular. Diamonds which are nearly round due to the stepping tendency of octahedrons are commonly found coated in nyf, a gum-like skin; the combination of stepped faces, growth defects, and nyf produces a "scaly" or corrugated appearance, and such diamonds are termed crinkles. A significant number of diamonds crystallize anhedrally: that is, their forms are so distorted that few crystal faces are discernible. Some diamonds found in Brazil and the Democratic Republic of the Congo are cryptocrystalline and occur as opaque, darkly colored, spherical, radial masses of tiny crystals; these are known as ballas and are important to industry as they lack the cleavage planes of single-crystal diamond. Carbonado is a similar opaque microcrystalline form which occurs in shapeless masses. Like ballas diamond, carbonado lacks cleavage and its specific gravity varies widely, from 2.9–3.5. Bort diamonds, found in Brazil, Venezuela, and Guyana, are the most common type of industrial-grade diamond, also cryptocrystalline or otherwise poorly crystallized, but possessing cleavage, translucency, and lighter colors.

Due to its great hardness and strong molecular bonding, a cut diamond's facets and facet edges are observably the flattest and sharpest. A curious side effect of diamond's surface perfection is hydrophobia combined with lipophilia. The former property means a drop of water placed on a diamond will form a coherent droplet, whereas in most other minerals the water would spread out to cover the surface. Similarly, diamond is unusually lipophilic, meaning grease and oil readily collect on a diamond's surface. Whereas on other minerals oil would form coherent drops, on a diamond the oil would spread. This property is exploited in the use of so-called "grease pens," which apply a line of grease to the surface of a suspect diamond simulant. Diamond surfaces are hydrophobic when the surface carbon atoms terminate with a hydrogen atom and hydrophilic when the surface atoms terminate with an oxygen atom or hydroxyl radical. Treatment with gases or plasmas containing the appropriate gas, at temperatures of 450 C or higher, can change the surface property completely. Naturally occurring diamonds have a surface with less than a half monolayer coverage of oxygen, the balance being hydrogen and the behavior is moderately hydrophobic. This allows for separation from other minerals at the mine using the so-called "grease-belt".[4]

Diamond is so strong because of the shape the carbon atoms make. It's a very strong 3D shape, each carbon atom having four joined to it with covalent bonds.

Material properties of diamond


Diamond is transparent to opaque, optically isotropic, 3D-crystalline carbon. It is the hardest naturally occurring material known, owing to its strong covalent bonding, yet its toughness is only fair to good due to important structural weaknesses. The precise tensile strength of diamond is unknown. However, strength up to 60 GPa has been observed, and its theoretical intrinsic strength has been calculated as 90 to 225 GPa, depending on the crystal orientation.[1] Diamond has a high refractive index (2.417) and moderate dispersion (0.044), properties which are considered carefully during diamond cutting and which (together with their hardness) give cut diamonds their brilliance and fire. Scientists classify diamonds into two main types and several subtypes, depending on the nature of crystallographic defects present. Trace impurities substitutionally replacing carbon atoms in a diamond's crystal lattice, and in some cases structural defects, are responsible for the wide range of colors seen in diamond. Most diamonds are electrical insulators but extremely efficient thermal conductors. The specific gravity of single-crystal diamond (3.52) is fairly constant. Contrary to a common misconception, diamond is not the most stable form of solid carbon; graphite has that distinction.

How to Evaluate a Diamond Grading Certificate


A diamond grading certificate or report is like a "fingerprint" for the diamond, describing the stone in technical detail so that its value and identity can be verified. It does not assign monetary value to the stone, as an appraisal does, and is only provided for loose diamonds. If you are purchasing a diamond, it's important to ask for and know how to read a grading report so you can make sure you're getting what you pay for.

Tuesday, April 14, 2009

Silvermist Diamonds


Combining colours of morning mist with the twilight shades of night. Brilliant white and grey diamonds set in argentium silver, Silvermist Diamonds, unveil the mystery.

Birthstone
April
Brand
Silvermist Diamonds
Diamond
1/3 carat
Material
Silver
Stone setting
Pave
Stone shape
Round
Stone type
Diamond

A Historical Panorama: Diamond's Role in Adornment


Diamond's place in cultural history is explored through its presence in legend and mythology, as well as its role in art and adornment. Breathtaking jewelry and artifacts highlight the fascinating cultural and historical significance of diamond and show how diamond and its myths traveled from India to the West. The oldest cultural object in the exhibition, a Roman ring set with two rough diamonds, is dated from 300 A.D. A major cultural significance of diamond is reflected through the chronology of the diamond betrothal rings. A collection of five centuries of diamond betrothal rings, on loan from Benjamin Zucker, celebrates this tradition and demonstrates the evolution of diamond fashioning. On display from the middle ages, the Badge of the Order of the Garter is an important example of early use of diamonds in British royalty.

[Photo of a sampling of naturally colored diamonds from the Aurora Collection. On loan from Aurora Gems, Inc., New York. Photograph © Harold and Erica Van Pelt. The transition from "royal diamonds" to "everyone's diamonds" at the turn of the century is examined. Diamond's connotation of class, culture, and wealth captured the heart of Hollywood and is seen in a video of film clips and still photographs of diamond in Hollywood. Famous jewels of celebrities will be displayed in this area as well, including a diamond bracelet owned by Joan Crawford, an art deco shoulder brooch previously owned by Sir Elton John, and a ring worn by Ginger Rogers. Also included is a ring worn by Hillary Rodham Clinton at the 1993 and 1997 presidential inaugurals, a bracelet from the 17th Century owned by Mamie Doud Eisenhower, and pieces from New York fashion maven, Diana Vreeland.

A major highlight of the exhibit is the walk-in diamond vault, a high security, self-contained bank-style vault housing the most fabulous and notable diamonds of the exhibit. Among these are the 407.48-carat Incomparable (on loan from Zale Corporation, Dallas, Texas; Marvin Samuels, Premier Gem Corporation, New York; and Louis Glick, Co, New York); the Aurora collection, 260 naturally colored diamonds (on loan from Aurora Gems, New York); The Pumpkin Diamond, the largest fancy orange diamond ever recorded (on loan from Harry Winston); the Eureka, considered to be the "discovery diamond" that sparked a revolution in diamond production; and the Arkansas, an example of an exemplary diamond found in the U.S.

Of historic importance, the Cullinan Blue necklace created for Lady Annie Harding Cullinan, wife of Premier Mine owner, Sir Thomas Cullinan of South Africa. The Cullinan Blue is on loan courtesy of S. H. Silver Co., Inc., Menlo Park, California. The Tiffany bow corsage ornament is on display as well as an exquisite collection of tiaras from the 19th and 20th Centuries.
Diamond Exploration, Mining, and Marketing

The history of diamond exploration, mining and marketing is described in this part of the exhibit, detailing diamonds' transition from mine, to dealer, to their use in industry or as gems. Mining and exploration have extended to every continent but Antarctica, and have developed into a large, technically sophisticated diamond mining industry. Models will be on display that demonstrate the three types of mining: kimberlite pipe, or underground mining; alluvial, or gravel mining; and marine, or beach and undersea mining.

Visitors will get an inside look at the world of diamond exploration through "Diamonds in the Tundra," a video documentary following the fast-paced, high-priced exploration for diamonds ongoing in the Northwest Territories and Arctic reaches of Canada.

Diamond Report 2008

Diamond Report 2008

4Shared Link

Rapid Share Link

About Diamonds (Diamond FAQ)



The Four most popular factors used to
measure diamond quality are: Color, Carat,
Clarity and Cut. Topics to discuss are Diamond
Color Clarity Grade, Diamond Grades Quality Information & Diamond Grade Scale.

Diamond Color: Degree to which a diamond is colorless
Diamond Clarity: Presence of inclusions in a diamond
Diamond Carat: Weight of a diamond
Diamond Cut: Angles and proportions of a diamond

browse our exquisite DIAMOND JEWELRY
Diamond Jewelry

A Huge collection
of Gold Diamond Jewelry
in many styles.

Color: (The color used in this diagram is for presentation purposes and is not actual color.)

Many experts name color as the number one consideration in choosing a diamond. A diamond's color is graded on an alphabetical scale from D-Z, with D being absolutely colorless and Z being light yellow. Beyond "Z", a diamond is considered to be an exotic or "Fancy" color.

DIAMOND COLOR SCALE
D E F G H I J K L M N O P Q R S T U V W X Y Z
Colorless Near Colorless Faint Yellow Very Light Yellow Light Yellow

Since color differences can be so subtle, they are impossible to determine by the untrained eye. To grade a diamond, gemologists often place it on a white background next to another diamond that has been previously graded.

If all other factors are equal, the less color in a diamond or the higher color rating, the more valuable a diamond becomes. Likewise, as the amount of color increases, the price of a diamond decreases (though this does not necessarily reduce the beauty of a diamond.)

Clarity

All diamonds have identifying characteristics, but most are invisible to the naked eye. To view a diamond, experts use a 10x magnifying loupe which allows them to see the appearance of tiny crystals, feathers or clouds. These natural phenomena are called inclusions.There are five categories in class that anyone interested in purchasing a diamond should be aware of when grading clarity.



DIAMOND CLARITY SCALE

FL


IF


VVS1


VVS2


VS1


VS2


SI1


SI2


I1


I2


I3

Flawless-
Internally Flawless


Very Very Slightly
Imperfect


Very Slightly
Imperfect


Slightly Imperfect


Imperfect



FL (Flawless) - IF (Internally Flawless)
Flawless Diamonds reveal no flaws on the surface or internally are the rarest and most beautiful gems.

Internally Flawless Diamonds reveal no inclusions and only insignificant blemishes on the surface under 10x magnification.

VVS1 - VVS2 (Very, Very Slightly Included)
Very difficult to see inclusions under 10x magnification. These are excellent quality diamonds.

VS1 - VS2 (Very Slightly Included)
Only looking through a 10X loupe can pinpoint the inclusions in this category and are nearly impossible to see with the naked eye. These are less expensive than the VVS1 or VVS2 grades.

SI1 - SI3 (Slightly Included)
Diamonds with inclusions easily identified under 10x magnification. Finding flaws in this category with the naked eye is difficult. The gems in this category maintain their integrity, depending on the location of the inclusions.

I1 - I3 (Included)
Diamonds with inclusions which may or may not be easily seen by the naked eye. The flaws on the stones in this category will have some effect on the brilliance of your diamond.

Carat: (This diagram is for presentation purposes and is not to scale)


Carat is often confused with size even though it is a measure of weight. The cut of a diamond can make it appear larger or smaller than its actual weight.

One carat is the equivalent of 200 milligrams. One carat can be divided into 100 "points". A .75 carat diamond is the same as 75 points or a 3/4 carat diamond. Since larger diamonds are rarer than smaller diamonds, the value rises exponentially with carat weight.

Cut


Cut actually refers to two aspects of a diamond. The first is its shape (round, marquise, etc) the second is how well the cutting has been executed.

A diamond's cut will most certainly influence its fire (the lovely rainbow colors that flash from within) and brilliance (the liveliness and sparkle), as well as its perceived size and even, to some degree its apparent color. Different cuts reflect light in different angles. A diamond must be cut in a geometrically precise manner to maximize its brilliance.

Blue Diamonds


Fancy blue diamonds are available in a wide range of shades, from the blue of the sky to a more "steely" colour than sapphire.

Limited quantities of fancy blue diamonds are recovered from the Argyle mine

Yellow Diamonds




Fancy yellow diamonds come in a broad range of shades ranging from light yellow to a rich canary colour.

A limited quantity of fancy yellow diamonds is recovered from the Argyle mine.

Champagne Diamonds



Champagne diamonds are naturally coloured diamonds that are produced in a wide range of colours from light straw to rich cognac.

The 4C's of colour, cut, clarity and carat weight apply to coloured diamonds just as they do to colourless diamonds except the intensity of colour, not lack of it, plays a greater part in the valuation.





Argyle Diamonds created the following scale specifically for champagne diamonds. The diamonds are graded on a C1-C7 colour scale. C1 and C2 represent light champagne, C3 and C4 medium champagne, and C5 and C6 dark champagne. The fancy cognac diamond is graded C7.

White Diamonds



White diamonds are produced by mines all over the world in a wide variety of shapes and sizes.The white diamonds recovered from the Argyle mine are particularly brilliant and of high quality.




White diamonds with secondary pink colour

The Argyle mine also produces white diamonds with secondary pink colour that command a higher price per carat. In an effect similar to that described of pink champagne diamonds, the white diamond will display slight to bold flashes of pink when viewed from the top. A higher price is commanded for pink secondary colour depending on its depth and strength, because pink is one of the most rare colours found in diamonds.

Pink Diamonds




The pink diamond is the world's most rare and valuable diamond.The Argyle mine is the world's foremost source of unrivalled intense pink diamonds, producing 95% of the world's supply. However, an extremely small proportion of Argyle Diamonds production is Pink colour, in fact less than one tenth of 1% is classified Pink.



The legend of Argyle pink diamond has grown over the past ten years. At the 1989 Christie's auction in New York a 3.14 carat Argyle pink sold for $1,510,000. Privately, Argyle has sold pink diamonds for up to $1 million a carat.


For years the white diamond was considered the world's most beautiful diamond, until the discovery of the Argyle mine heralded the arrival of the Argyle pink diamond. Never before had pink diamonds displaying such intense shades of colour been seen. The pink diamonds of India, Brazil and Africa were characteristically light in colour and paled even further when placed beside the intensely pink Argyle diamonds. The natural colour diamonds have in fact been around as long as the classical whites but in much smaller quantities and never in great demand.

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The Argyle pink diamond comes in shades ranging from delicate pastel rose to robust raspberry and full-blooded purple-reds. The prices per carat are determined by the intensity of colour. Argyle selects only its most vibrant pink diamonds for polishing at its head office in Perth. There, the stones are polished in a wide range of cuts, such as round brilliant, marquise, oval and pear, to enhance their natural beauty. Polished pink diamonds are available in the same size ranges as traditional commercial sizes.


Once a year, Argyle Diamonds issues a special release of outstanding pink diamonds that are sold by special bids in the international and invitation-only, Pink Diamond Tender.

What is a Carat?

A unit of weight for precious stones, equal to 200 milligrams. It is thought that the name carat was derived from the carob tree. Carob trees are native to the Old World (Asia, Africa, and Europe) and are known for its uniformly consistent small seeds. Gemstones, including diamonds were weighed for years against these seeds. A diamond that weighs 100 points would also be 1 carat. 1 carat is equal to 100 points. A diamond that is larger than one carat would be listed as a whole number plus the number of points it was. For example a diamond that was 1 carat and 25 points would be listed as 1.25 carats.

What Do Diamonds Look Like?



How do you know if you've found treasure in our Arkansas diamond mine? First study the basic attributes of diamonds found at the Crater:

Shape:
Diamonds found at the Crater are typically smooth and well rounded. Their shape resembles a polished stone with smooth sides and rounded edges.

Size:
The average size of a diamond is about the size of a paper match head, approximately 20 - 25 points. Points are an increment of measurement of diamonds. There are 100 points in a carat. Look for something small. A 1-carat diamond is about the size of a green pea.
What might you find when digging for diamonds at the Crater?

Appearance:
Diamonds feel like they have an oily film on them. This characteristic prevents diamonds from being dirty. Diamonds have a metallic luster like new steel or lead. They will not be clear like glass. They do not have a solid dull look like the Jasper rocks. Diamonds are translucent. You can typically see into them but not through them.

Color:
The most common colors of diamonds are white, yellow and brown.

The park offers free rock and mineral identification at the Diamond Discovery Center. Diamonds are weighed and certified free of charge for the finder

Why Diamonds Can Be Found at Crater of Diamonds


Ever wonder why the earth produces diamond mines and why we have a field in Arkansas where diamonds are found? The story of the diamonds found at the Crater of Diamonds State Park begins over 3 billion years ago with the formation of diamonds as the stable form of carbon in the earth’s mantle. At the tremendous pressures and temperatures some 60 to 100 miles below the earth’s surface, diamond crystallized from carbon, and under those conditions it remained stable.

During the past 3 billion years, many geologic changes have taken place on the surface of the earth. Crust formed and was destroyed, continents formed and migrated, and mountain ranges were built and eroded away. About 300 to 250 million years ago, the continent we now call South America collided with the southern portion of present day North America. This collision formed the Ouachita Mountains from sediments that were deposited in a deep ocean environment. The Ouachitas began to erode and during the Cretaceous Period (144 to 66 million years ago), the southern area of this eroded mountain range was covered by seas and the area of the Park was near-shore, but under shallow seawater. About 100 million years ago, an instability in the Earth’s mantle caused the movement of gas and rock to the surface. This volcanic vent, known as the “Prairie Creek” diatreme by geologists, rose rapidly through the upper mantle and crust, carrying with it fragments of mantle and crustal rocks and minerals, until it came near enough to the surface to explode due to the release of gases. When it exploded, it created an 83-acre funnel-shaped crater with sides sloping inward at about 45 degrees. Much of the airborne material formed by the initial explosion fell back into the vent. The speed of rise of the mass allowed the diamonds to be preserved in this material.

Geologists calculate that only about 160 feet of the original vent has been eroded away, concentrating the heavy minerals, including diamond, in the present day soil. At the Crater, diamonds are often found loose in the soil, having been released during the rapid weathering of this unstable mantle rock.

Quality Diamonds


Spence diamonds are purchased direct from our buying office in the heart of Antwerp’s Diamond District. We set up shop there in 1980 and have maintained professional relationships with the world’s premiere diamond cutting and polishing houses ever since. They know our quality standards, they know we buy a lot of diamonds and they appreciate that we pay our bills on time. For all of these reasons, Spence has moved to the top of the pecking order when new diamond lots become available.

When it comes to choosing your diamond, Spence ring designs fit a variety of different shapes and sizes. Some styles are more suited to a particular shape than others, so should you choose to have us build your ring, a diamond consultant will be happy to act as your trusted advisor in finding a combination that works.

What women need to know about shopping at Spence.

VISIBLY BETTER DIAMONDS, OBVIOUSLY BETTER PRICES

Wednesday, April 8, 2009

Oval Cut Diamond

The oval cut diamond is actually an elongated brilliant cut diamond and is traditionally set with two smaller diamonds flanking the center diamond on either side. Although the oval diamond is not as popular as a stand alone diamond in a solitaire engagement ring, it is very sought after in a three-stone diamond engagement ring. When the oval diamond is cut well, it has tremendous brilliance and fire.

Because of its elongated shape and curvature, it is considered a very classical and elegant diamond. The type of setting you choose for your oval-shaped diamond will greatly impact the impression it gives. Choosing a pave diamond ring for your oval diamond, or smaller flanking diamonds will greatly enhance the overall look.

Princess Cut Diamonds

The princess cut diamond is the second most popular diamond shape after the round diamond. Traditionally, the princess cut diamond has been a diamond shape that does not allow for maximum beauty and brilliance. This is partially due to its four corners which will allow too much light to leak out of the diamond instead of being directed back to the eye in the form of brilliance. Many diamond companies and manufacturers have attempted to combat this by creating modified square diamonds with tapered edges. The problem with this approach is the fact that it destroys the beauty and elegance that has always been associated with a true square diamond.

Round Brilliant Cut Diamond

The round diamond is the most traditional and popular of all diamond shapes. Approximately 80% of all loose diamonds being sold in the marketplace are round cut diamonds. A round cut diamond has a total of 58 facets, 33 on the top portion called the crown and 25 facets on the bottom called the pavilion. A round diamond that is cut to ideal cut diamond parameters will be the most beautiful and brilliant of all the diamond shapes. It is for this reason that round diamonds are most often set in solitaire, four-prong engagement ring settings to showcase their brilliance.

Tutorial on Loose Diamond Shapes


When choosing a diamond ring for that special woman in your life, one of the most important choices you will have to make is the shape of the diamond itself. Every diamond shape has its own unique look and should therefore be carefully considered before making a purchase. Many women focus on choosing a diamond ring that flatters the shape and length of their fingers.

We have put together some information on the most popular diamond shapes in the marketplace today.


Famous Diamonds


The world's most famous diamonds are its largest diamonds. At staggering weights up to thousands of carats, these diamonds have been cut, re-shaped and sold many times, contributing to their rich, interesting histories. Despite diamond's natural, clear brilliance, some of these stones have a dark side.
  • The Cullinan - This 3,106-carat diamond is the largest diamond ever found. It was discovered in 1905 in Transvaal, South Africa. In 1907, the diamond was presented to King Edward VII of England. Later, it was cut into nine major stones, including the 530.20-carat Star of Africa diamond that is set in the Royal Scepter displayed in the Tower of London.
  • The Hope Diamond - Possibly the most famous diamond in America, this 45.52-carat diamond is on display at the National Museum of Natural History in Washington D.C. Its history dates back to the 1600s, when it was originally a 112.1875-carat diamond. In 1668, it was purchased by King Louis XIV, of France. It is believed to have been originally found in the Kollur mine in Golconda, India. The diamond was recut in 1673, creating a smaller 67.125-carat stone. You can learn more about the Hope Diamond at the Smithsonian.
  • ­
  • The Excelsior - Perhaps the second-largest diamond ever found, the Excelsior was found in 1893 in South Africa. The original stone weighed about 995 carats. In 1904, I.J. Asscher and Company of Amsterdam cut the Excelsior into 21 polished stones weighing between 1 and 70 carat­s.
  • The Great Mogul - Believed to be the third-largest uncut diamond ever found, it was discovered around 1650. Its original size is said to have been 787.50 carats, but it was cut to just 280 carats. The diamond is named for Shah Jehan, who built the Taj Mahal. After the diamond was cut, he fired the cutter for doing such a poor job. Mysteriously, the whereabouts of the Great Mogul diamond are unknown today.

Hope Diamond
Photo Courtesy Smithsonian Institution
The Hope Diamond­

Most people can only dream of owning a diamond as large as these famous stones -- but synthetic diamonds could change that. In the next section, we'll learn about different synthetic diamonds.

Synthetic Diamonds

For people who can't afford real diamonds or want a 100-percent guarantee that their diamond is conflict-free, synthetic diamonds are a good substitute. For many years, the only synthetic option available was cubic zirconia, but now consumers can also choose from Moissanite and man-made diamonds.

Orange and yellow synthetic diamonds like these are less expensive than colored natural diamonds, which are quite rare.
Photo ­courtesy Carnegie Institute of Washington
Orange and yellow synthetic diamonds like these are less expensive than colored natural diamonds, which are rare.
Cubic zirconia, commonly called CZ, is a laboratory gem that has been on the market since 1976. It's a hard gem (8.5 on the Mohs Scale), but it's not as hard as diamond. On the one hand, CZ is compositionally superior to diamond. CZ has greater brilliance and sparkle, it's entirely colorless and it has no inclusions. However, most consumers agree that CZ is simply too perfect -- it looks artificial even to the naked eye. Because of this, some CZ manufacturers have started producing the gem with colored tints and inclusions so that it more closely resembles diamond.
Moissanite has become CZ's biggest synthetic rival. Moissanite became available in 1998, and it's even more similar to diamond in composition and appearance. Moissanite is harder than CZ, but at 9.5 on the Mohs Scale, it is still softer than diamond. Moissanite's color is faintly yellow or green, and the tint becomes more apparent in larger stones. It also has small, stretch-mark-like inclusions that form during its growing process. Like CZ, Moissanite is more radiant than diamond, but this quality is considered a disadvantage rather than an advantage.
A LifeGem like this yellow diamond commemorates a deceased loved one.
Photo courtesy LifeGem
A LifeGem like this yellow dia­mond commemorates a deceased loved one.

­ The closest synthetic approximation to diamond is a man-made diamond. Unlike CZ and Moissanite, man-made diamonds are pure carbon. The Gemological Institute of America (GIA) recognizes these as real diamonds from a compositional perspective. But, the man-made diamonds don't have the rich geological history that natural diamonds do. Laboratories simulate the heat and pressure from the Earth's mantle that create natural diamonds. For the synthetic manufacturers and the consumers, diamonds come down to a matter of time and money: days versus millions of years, thousands of dollars versus tens of thousands of dollars or more (man-made diamonds sell for about 30 percent less than natural ones) [source: MSN]. If you want a uniquely colored, relatively inexpensive diamond (it will cost less than a natural colored diamond), you can find man-made ones in shades of orange, yellow, pink and blue. Finding a large diamond will prove a greater challenge -- most man-made diamonds weigh less than one carat. If you want the best synthetic has to offer, man-made diamonds are a no-brainer. Even jewelers can have a hard time telling them apart from natural ones. To prevent retailers from passing off man-made diamonds as natural ones, the GIA is selling machines that will help jewelers easily distinguish between the two. ­

It may come as no surprise that the developer behind these machines is none other than the king of the natural diamond industry: De Beer

Cutting Diamonds

Th­ere are special techniques that are used to cut and shape a diamond before it gets to the jewelry store. Diamond cutters use these four basic techniques:
  1. Cleaving - To cut a rough diamond down to a manageable size, the cutter must cleave it along the diamond's tetrahedral plane, where it is the weakest. A wax or cement mold holds the diamond in place while the cutter carves a sharp groove along the plane. The cutter places a steel blade in the groove and forcefully strikes it, cutting the rough diamond in two.
diamond cleaving
  1. Sawing - Sometimes, diamonds have to be cut where there is no plane of weakness, which cannot be done with cleaving. Instead, the cutter saws the diamond using a phosphor-bronze blade rotating at about 15,000 rpm. Lasers can also be used to saw diamonds, but the process takes hours. During the sawing step, the cutter decides which parts of the diamond will become the table (the flat top of the stone with the greatest surface area) and the girdle (the outside rim of the diamond at the point of largest diameter). Then, he proceeds to cutting.
  2. ­
  3. Bruiting/Cutting - This technique gives diamonds their shape. When diamonds are cut by hand, the technique is called bruiting -- cutting refers to bruiting by machine. When the cutter shapes diamonds by hand, he relies on the diamond's hardness as his tool -- he uses diamonds to cut diamonds. He uses a small, stick-like instrument with a cement-filled bowl at the tip to hold the diamond. The diamond is inserted in cement with just one corner exposed. Using one of these sticks in each hand, the cutter rubs the exposed diamond parts together to bruit them. In the mechanical process, the diamond is placed in a lathe, and another diamond in the lathe rubs against it to create the rough finish of the g­irdle.

The Properties of Diamonds

Diamonds are found as rough stones and must be processed to create a sparkling gem that is ready for purchase.

Rough diamonds in a hand.
Photo courtesy Getty Images
These rough stones will become dazzling diamonds after they are cut and polished.

As mentioned before, diamonds are the crystallized form of carbon created under extreme heat and pressure. It's this same process that makes diamonds the hardest mineral we know of. A diamond ranks a 10 on the Mohs Hardness Scale. The Mohs Scale is used to determine the hardness of solids, especially minerals. It is named after the German mineralogist Friedrich Mohs. Here's the scale, from softest to hardest:

  1. Talc - easily scratched by the fingernail
  2. Gypsum - just scratched by the fingernail
  3. Calcite - scratches and is scratched by a copper coin
  4. Fluorite - not scratched by a copper coin and does not scratch glass
  5. Apatite - just scratches glass and is easily scratched by a knife
  6. Orthoclase - easily scratches glass and is just scratched by a file
  7. Quartz - (amethyst, citrine, tiger's-eye, aventurine) not scratched by a file
  8. Topaz - scratched only by corundum and diamond
  9. Corundum - (sapphires and rubies) scratched only by a diamond
  10. Diamond - scratched only by another diamond

Even though diamond is only one level higher on the scale than corundum, diamond can be anywhere from 10 to hundreds of times harder than this class of gems.

It is the molecular structure of diamonds that makes them so hard. Diamonds are made of carbon atoms linked together in a lattice structure. Each carbon atom shares electrons with four other carbon atoms, forming a tetrahedral unit. This tetrahedral bonding of five carbon atoms forms an incredibly strong molecule. Graphite, another form of carbon, isn't as strong as diamond because the carbon atoms in graphite link together in rings, where each atom is only linked to one other atom.

Carbon and Kimberlite

Carbon is one of the most common elements in the world and is one of the four essentials for the existence of life. Humans are more than 18 percent carbon. The air we breathe contains traces of carbon. When occurring in nature, carbon exists in three basic forms:
  • Diamond - an extremely hard, clear crystal
  • Graphite - A soft, black mineral made of pure carbon. The molecular structure is not as compact as diamond's, which makes it weaker than diamond.
  • Fullerite - A mineral made of perfectly spherical molecules consisting of exactly 60 carbon atoms. This allotrope was discovered in 1990.

How Diamonds Work


Notice the diamond jewelry that takes up the majority of the showcase and the number of people hovering over the counters trying to pick out diamonds for their loved ones. There will surely be a salesperson explaining the "4 Cs" -- cut, clarity, carat and color -- to a young shopper, and explaining why one diamond is better than the one right next to it. Why all the fuss over diamonds?
A diamond is just carbon in its most concentrated form. That's it -- carbon, the element that makes up 18 percent of the weight of your body. In many countries, including the United States and Japan, there is no other gemstone as cherished as the diamond, but in truth, diamonds are no rarer than many other precious gems. They continue to demand higher market prices because the majority of the diamond market is controlled by a single entity.




Fashion News Salma and Goldie - amfAR's Diamond Duo

The always-gorgeous Salma Hayek stunned the crowd with both her auctioning skills and a stunning Boucheron statement necklace with a diamond rosette. And fellow auctioneer, Goldie Hawn, always lights up a room, but her lobster-bib sized diamond necklace with gemstone accents took things to an entirely new level.

Jeffrey Wright, Danny Glover, Harry Belafonte and directors, Oliver Stone and Terry Gilliam, helped the diamond-clad event chairs raise $1.8m for amfAR, auctioning off items that included a stint on the Hayek-produced show Ugly Betty and a one-of-a-kind Cartier diamond cuff with Hayek's signature.

Champagne diamond ring by Kiah

A ring from Kiah Diamond Jewellery's champagne diamond jewelry collection consisting of pendants, earrings, bracelets, bangles and rings. Price: Rs 7,500 onwards and available at all Kiah showrooms across the nation.
Product Details
Metal Information : gold

Item Category : Rings

Stone Information : champagne diamonds

Color : brown

EGL 0.97 CT ROUND DIAMOND ENGAGEMENT RING PLATINUM NEW EGL 0.97 CT ROUND DIAMOND ENGAGEMENT RING PLATINUM NEW

0.97 ct. K I1 Princess Cut Diamond Solitaire Ring:

A single diamond solitaire ring will always be adored for its classic and elegant beauty. This 0.97 ct. sparkling princess cut diamond is masterfully prong set in a well crafted Gold ring. Available in yellow and white gold.

Genuine Diamond 9K 9ct Solid Yellow Gold Filigree Ring


PRoduct information
Metal: 9k Yellow Gold (stamped 9K)
Band Width(bottom): 1.8mm
Size: Australian O / USA 7
See below for resizing options
Total Weight: 1.78g
gemstone INFORMATION
Gemstone(s): Diamond
Gemstone(s) Quantity: 12
Gemstone(s) Colour: H-I (near white)




SANGINI DIAMOND JEWELLERY - NKDTC008A


About this Product

  • No. of diamonds -15
  • Dia wt - 0.38
  • Gross wt. - 2.0
  • Diamond clarity SI
  • Diamond color - GH
  • Gold Kt - 18KT
  • All wt. approx
  • All Sangini products are supported by IGI certification

SANGINI DIAMOND JEWELLERY - NKDTC001A


About this Product

  • No. of diamonds -11
  • Dia wt - 0.43
  • Gross wt. - 1.94
  • Diamond clarity SI
  • Diamond color - GH
  • Gold Kt - 18KT
  • All wt. approx
  • All Sangini products are supported by IGI certification
  • Price Rs=26000

Royale Bangle


Diamonds and Emaralds in perfect harmony to make a piece of Art.Gold 8 gms/14K.Emarald .25 Carat.
Diamond .25 Carat.
All the jwellery come with the certificate of Guarantee.

How to Care for your Diamonds

Diamonds are often thought to be unshatterable. Unfortunately, this is not the case. Here are some useful handling and care tips.
  • Diamonds are brittle: If you hit a diamond hard, they WILL crack or chip if mishandled. Don't wear your diamond when doing rough work.

  • Storage: Store diamonds separately. When stored with other jewelry, diamonds may scratch other jewelry (or each other).

  • Cleaning: The best method for cleaning is a jeweler's polishing cloth. Most jewelers will clean your diamond ring for free if you are making another purchase in the store.

How Diamonds are Treated

Diamonds are often treated. If you are concerned about getting true value for your money, know what you are getting.
  • Filled for clarity: Diamonds with inclusions are sometimes filled with glass to make them appear clearer. Yehuda Diamonds have undergone this treatment. Filler can be damaged by heat, ultrasonic cleaning, and by re-tipping. The filling does not repair the inclusion, it just makes it less visible.

    If you look at a filled diamond closely, rotate it under light, you should be able to notice a bluish flash. Yehuda will usually refill your diamond for free if it is ever damaged. Check for guarantees before buying such a diamond.

  • Irradiated for color: Can be affected by heat.

  • Painted for color: Can be painted to offset a yellow tinge. The paint wears off rather quickly.

  • Ask if the diamond you are considering buying is treated. Getting a notarized statement from your jeweler saying that your diamond in not treated is recommended. This is like having the jeweler swear under oath that to his/her knowledge that the diamond is not treated. Several states have disclosure acts requiring dealers to tell you about these treatments.

How to Examine a Diamond

To accurately judge the quality of a diamond, it is advisable to use more than the naked eye. Here are common ways to examine a diamond.
  • Microscope/Loop: To examine inclusions, one uses either a microscope or a 10x magnifying glass called a jeweler's loop. This enables one to see inclusions in stones. Most dealers will let you use theirs.

  • Diamond Tester: A diamond tester uses light to verify that the stone you are examining is really a diamond. It does not guarantee quality type of stone. Most testers will still work when the stone is mounted.
Certification: If you are unsure of your diamond knowledge or the jeweler you are buying from, get a certified Diamond. The best known and reliable certification is from GIA (Gemological Institute of America) or EGL (European Gemological Laboratory). Be aware that certificates will cost you an extra $100-$200 on average.

Quality Diamond Information

Diamonds are graded by four characteristics: cut, carat (weight), clarity, and color. All four of these properties determine how much a diamond is worth.
  • Cut - What is the proportion of the diamond? Round brilliant diamonds are commonly cut with 58 facets. The better proportioned these facets are on the diamond, the more light will be reflected back to the viewer's eye. This is extremely important. When cut properly, the diamond will sparkle more. Diamond cuts are measured by the table percentage, so always ask for it. A good table percentage is between 55-60%. Cut also refers to the shape such as: round, pear, and oval.
    If you are having a diamond mounted, write down the measurements of your stone. Measurements never change. Measure the stone after it is mounted and verify that it matches the appraisal and/or certificate.

  • Carat - How big is the diamond? Larger diamonds often cost more per carat due to their size. There are 100 points to a carat. Hence a 50 point diamond is 1/2 a carat. (There are 5 carats to a gram.) Always get the actual point size of a diamond rather than a fractional weight. Sometimes jewelers will try to sell a .90 diamond as a 1 carat diamond. A .90 diamond should be substantially less expensive.

  • Clarity - How clear is the stone? Clarity ranges from flawless (perfect) to I (included). Here is a chart:
      Flawless: perfect inside and out
      Internally Flawless: may have minor blemishes on the outside
      VVS1, VVS2: have very very small inclusions. VVS1 inclusions can only be seen through the pavilion. VVS2 inclusions are more visible.
      VS1, VS2: have very small inclusions. VS1 inclusions are harder to see than VS2.
      SI1, SI2, SI3: have small inclusions
      I1, I2, I3: have inclusions visible to the naked eye

  • Color: Diamond colors generally range from D - X for white and yellow diamonds. D is the whitest. Around S they become "Fancy" yellow Diamonds. One can also find green, pink, red, blue and brown diamonds - though these are usually irradiated.

    Be certain to ask: Do you guarantee the color and clarity of your stones? Many states allow dealers to be off by one color and/or one clarity.