Facts about Diamonds

The techniques for cutting diamonds have been developed over hundreds of years, with perhaps the greatest achievements made in 1919 by mathematician and gem enthusiast Marcel Tolkowsky.

Round brilliant diamonds, the most common, are guided by these specific guidelines, though fancy cut stones are not able to be as accurately guided by mathematical specifics.

The Diamond Trading Company, or DTC, is a subsidiary of De Beers and markets rough diamonds produced both by De Beers mines and other mines from which it purchases rough diamond production.

The Gemological Institute of America (GIA) classifies low saturation yellow and brown diamonds as diamonds in the normal color range, and applies a grading scale from 'D' (colorless) to 'Z' (light yellow).

Intense yellow coloration is considered one of the fancy colors, and is separate from the color grades of white diamonds.

A diamond's gem quality, which is not as dependent on material properties as industrial applications, has invited both imitation and the invention of procedures to enhance the gemological properties of natural diamonds.

According to the GIA, who reviewed a random sample of 26,010 natural diamonds, 65 percent of the diamonds in the sample had no fluorescence.

The ore is crushed, during which care has to be taken in order to prevent larger diamonds from being destroyed in this process and subsequently the particles are sorted by density.

Diamonds can be sold already set in jewelry, or as is increasingly popular, sold unset ("loose").

Gemologists have developed rating systems for fancy colored diamonds, but they are not in common use because of the relative rarity of colored diamonds.

Diamonds occur most often as euhedral or rounded octahedra and twinned octahedra known as macles or maccles.

Diamonds do cut glass, but other materials above glass on Mohs scale such as quartz do also.

Diamonds are graded by the major societies on a scale ranging from flawless to imperfect.

Diamonds that have come to the Earth's surface are generally very old, ranging from under 1 billion to 3.3 billion years old.

The origin of our custom to use diamonds in rings, and more recently, in engagement rings, can be traced back to the Middle Ages and even the Romans.

The dispersion of white light into spectral colors, is the primary gemological characteristic of gem diamonds.

Today, diamonds are located in the diamond-rich density fraction with the help of X-ray fluorescence, after which the final sorting steps are done by hand.

Diamonds easily scratch other diamonds, but this damages both diamonds.

Before the use of X-rays became commonplace, the separation was done with grease belts; diamonds have a stronger tendency to stick to grease than the other minerals in the ore.

Diamonds do not show all of their beauty as rough stones; instead, they must be cut and polished to exhibit the characteristic fire and brilliance that diamond gemstones are known for.

Certain indicator minerals typically occur within diamondiferous kimberlites and are used as mineralogic tracers by prospectors, who follow the indicator trail back to the volcanic pipe which may contain diamonds.

Industrial use of diamonds has historically been associated with their hardness; this property makes diamond the ideal material for cutting and grinding tools.

The cutting and polishing of rough diamonds is a specialized skill that is concentrated in a limited number of locations worldwide.

Diamonds with unusual or intense coloration are sometimes labeled "fancy" by the diamond industry.

Around 1300, the flow of diamonds into Europe increased via Venice's trade network, with most flowing through the low country ports of Bruges, Antwerp, and Amsterdam.

The recent expansion of this industry in India, employing low cost labor, has allowed smaller diamonds to be prepared as gems than was previously economically feasible.

Diamonds sold through this process are known as conflict diamonds or blood diamonds.

Diamonds quickly became associated with divinity, being used to decorate religious icons, and were believed to bring good fortune to those who carried them.

A number of large diamonds have become historically significant objects, as their inclusion in various sets of crown jewels and the purchase, sale, and sometimes theft of notable diamonds, have sometimes become politicized.

Very small diamonds, known as microdiamonds or nanodiamonds, have been found in impact craters where meteors strike the Earth and create shock zones of high pressure and temperature where diamond formation can occur.

Diamonds were traded to both the east and west of India and were recognized by various cultures for their gemological or industrial uses.

A variety of impurities and structural imperfections cause different colors in diamonds, including yellow, pink, blue, red, green, brown, and other hues.

Diamonds which have been prepared as gemstones are sold on diamond exchanges called bourses.

Secondary sources of diamonds include all areas where a significant number of diamonds, eroded out of their kimberlite or lamproite matrix, accumulate because of water or wind action.

The hardness of diamonds contributes to its suitability as a gemstone.

Microdiamonds are now used as one indicator of ancient meteorite impact sites.

Diamonds are specifically renowned as a material with superlative physical qualities—they make excellent abrasives because they can be scratched only by other diamonds, Borazon, ultrahard fullerite, or aggregated diamond nanorods.

Such a campaign had become necessary to sell the large quantity of diamonds suddenly available because of the large diamond finds particularly in South Africa.

A volcanic pipe containing diamonds is known as a primary source of diamonds.

Jewelers often trade diamonds at negotiated discounts off the Rapaport price (e.g., "R -3%").

Some diamonds with "very strong" fluorescence can have a "milky" or "oily" look to them, but they are also very rare and are termed "overblues."

De Beers owns or controls a significant portion of the world's rough diamond production facilities (mines) and distribution channels for gem-quality diamonds.

The GIA labels diamonds that have more color than a 'Z' diamond "fancy," along with those that are any color other than yellow or brown.

Industrial diamonds are valued mostly for their hardness and heat conductivity, making many of the gemological characteristics of diamond, including clarity and color, mostly irrelevant.

Many cultures use divine intervention to explain the origin and creation of gemstones, and diamonds were no exception to this.

Natural diamonds have formed naturally within the earth.

Currently, trained gemologists with appropriate equipment are able to distinguish natural diamonds from simulant diamonds, and they can identify all enhanced natural diamonds.

Archaeological evidence from Yemen suggests that diamonds were used as drill tips as early as the fourth century B.C.E.

Once purchased by sightholders, diamonds are cut and polished in preparation for sale as gemstones.

Four characteristics, known informally as the four Cs, are now commonly used as the basic descriptors of diamonds: these are carat, cut, color, and clarity.

The prong setting consists of four or six 'claws' that cradle the diamond, allowing the maximum amount of light to enter from all angles, allowing the diamonds to appear larger and more brilliant.

The most familiar usage of diamonds today is as gemstones used for adornment.

The hardest diamonds in the world are from the New England area in New South Wales, Australia.

Other colors diamonds can fluoresce are green, yellow, and red but are very rare and are sometimes a combination of the colors such as blue-green or orange.

Diamonds have been known in India for at least 3000 years but most likely 6000 years.

DTC performs sophisticated sorting of rough diamonds into categories, and then sells bulk lots of rough diamonds to a limited number of sightholders a few times a year.

Perhaps the earliest symbolic use of diamonds was as the eyes of Hindu devotional statues.

Historically, diamonds were known to be found only in alluvial deposits in southern India.

The production and distribution of diamonds is largely consolidated in the hands of a few key players, and concentrated in traditional diamond trading centers.

The techniques for cutting diamonds have been developed over hundreds of years, with perhaps the greatest achievements made in 1919 by mathematician and gem enthusiast Marcel Tolkowsky.

Only a very small fraction of the diamond ore consists of actual diamonds.

About a third of all diamonds will glow under ultraviolet light, usually a blue color which may be noticeable under a black light or strong sunlight.

Diamonds can also form in other natural high-pressure, relatively low-temperature events.

Once diamonds have been transported to the surface by magma in a volcanic pipe, they may erode out and be distributed over a large area.

Diamonds are thought to have been first recognized and mined in India (Golconda being one of them), where significant alluvial deposits of the stone could then be found along the rivers Penner, Krishna and Godavari.

The Canadian Government has setup a body known as Canadian Diamond Code of Conduct: () to help authenticate Canadian Diamonds.

The attractiveness and high prices of natural diamonds have also brought out the darker of human nature, such as theft, violence, and the sale of conflict diamonds by African paramilitary groups.

Many fancy colored diamonds are now being cut according to these new styles.

The point unit—equal to one one-hundredth of a carat (0.01 carat, or 2 mg)—is commonly used for diamonds of less than one carat.

Synthetic diamonds are created by a man-made process.

Most other diamonds show more evidence of multiple growth stages, which produce inclusions, flaws, and defect planes in the crystal lattice, all of which affect their hardness.

Diamond enhancements are specific treatments, performed on natural diamonds (usually those already cut and polished into a gem), which are designed to better the gemological characteristics of the stone in one or more ways.

Diamonds can occur in nearly any color, though yellow and brown are by far the most common.

Diamonds have been adapted for many uses because of the material's exceptional physical characteristics.

Some diamonds, known as harzburgitic, are formed from inorganic carbon originally found deep in the Earth's mantle.

Diamonds which are not cut to the specifications of Tolkowsky's round brilliant shape (or subsequent variations) are known as "fancy cuts."

Diamonds (especially those with rounded crystal faces) are commonly found coated in nyf, an opaque gum-like skin.

Diamonds are cut into a variety of shapes that are generally designed to accentuate these features.

Until the late Middle Ages, diamonds were most prized in their natural octahedral state, perhaps with the crystal surfaces polished to increase luster and remove foreign material.

The diamond industry can be broadly separated into two basically distinct categories: one dealing with gem-grade diamonds and another for industrial-grade diamonds.

The GIA system uses a benchmark set of natural diamonds of known color grade, along with standardized and carefully controlled lighting conditions.

Most diamonds used as gemstones are basically transparent with little tint, or white diamonds.

Diamonds graded D-F are considered "colorless," G-J are considered "near-colorless," K-M are "slightly colored."

All else being equal, the price per carat increases with carat weight, since larger diamonds are both rarer and more desirable for use as gemstones.

Roughly 49 percent of diamonds originate from central and southern Africa, although significant sources of the mineral have been discovered in Canada, India, Russia, Brazil, and Australia.

Most uses of diamonds in these technologies do not require large diamonds; in fact, most diamonds that are gem-quality except for their small size, can find an industrial use.

Diamonds with higher color grades are rarer, in higher demand, and therefore more expensive, than lower color grades.

when placed for sale, indicating the mass of the diamonds in both earrings and not each individual diamond.

Colored diamonds contain impurities or structural defects that cause the coloration, while pure or nearly pure diamonds are transparent and colorless.

is a phrase used to describe the total mass of diamonds or other gemstone in a piece of jewelry, when more than one gemstone is used.

At present the annual production of gem quality synthetic diamonds is only a few thousand carats, whereas the total production of natural diamonds is around 120 million carats.

Instead, there are sharp jumps around milestone carat weights, as demand is much higher for diamonds weighing just more than a milestone than for those weighing just less.

In 2000, the WFDB and The International Diamond Manufacturers Association established the World Diamond Council to prevent the trading of diamonds used to fund war and inhumane acts.

Currently, trained gemologists can also distinguish between natural diamonds from synthetic diamonds.

The demand for industrial diamonds has long been satisfied in large part by synthetic diamonds, which have been manufactured by various processes for more than half a century.

The Gemological Institute of America (GIA) classifies low saturation yellow and brown diamonds as diamonds in the normal color range, and applies a grading scale from 'D' (colorless) to 'Z' (light yellow).

The popularity of diamonds has risen since the nineteenth century because of increased supply, improved cutting and polishing techniques, growth in the world economy, and innovative and successful advertising campaigns.

The market for industrial-grade diamonds operates much differently from its gem-grade counterpart.

Diamonds are embedded in drill tips or saw blades, or ground into a powder for use in grinding and polishing applications.

Diamonds become increasingly rare when considering higher clarity gradings.

Industrial-grade diamonds are either unsuitable for use as gems or synthetically produced, which lowers their value and makes their use economically feasible.

New York, however, along with the rest of the United States, is where almost 80% of the world's diamonds are sold, including at auction.

The most important being Antwerp, where 80% of all rough diamonds, 50% of all cut diamonds and more than 50% of all rough, cut and industrial diamonds combined are handled.

Diamonds can be identified via their high thermal conductivity.

The concentration of power only loosens at the retail level, where diamonds are sold by a limited number of distributors, known as sightholders, to jewelers around the world.

Oddly enough, diamonds graded Z are also rare, and the bright yellow color is also highly valued.

Today, because of the relative importance of carat weight in society, many diamonds are often intentionally cut poorly to increase carat weight.

The rise in popularity of diamonds as gems seems to have paralleled increasing availability through European history.

Synthetic diamonds are created by a man-made process.

Other early examples of betrothal jewels incorporating diamonds include the Bridal Crown of Blanche (ca.

During this time, the taboo against cutting diamonds into gem shapes, which was established over 1000 years earlier in the traditions of India, ended allowing the development of diamond cutting technology to begin in earnest.

Other specialized applications also exist or are being developed, including use as semiconductors: some blue diamonds are natural semiconductors, in contrast to most other diamonds, which are excellent electrical insulators.

The majority of commercially available synthetic diamonds are yellow in color and produced by so called High Pressure High Temperature (HPHT) processes.

Most inclusions present in gem-quality diamonds do not affect the diamonds' performance or structural integrity.

Consumers who purchase individual diamonds are often advised to use the four Cs to pick the diamond that is "right" for them.

Diamonds have been treasured as gemstones since their use as religious icons in ancient India.