Mathematically, the diameter in millimeters of a round brilliant should approximately equal to 6. 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.
Diamonds are cut into a variety of shapes that are generally designed to accentuate these features. Diamonds which are not cut into a round brilliant shape are known as "fancy cuts.
Newer cuts that have been introduced into the jewelry industry are the "cushion" "radiant" similar to princess cuts, but with rounded edges instead of square edges and Asscher cuts.
Many fancy colored diamonds are now being cut according to these new styles. Generally speaking, these "fancy cuts" are not held to the same strict standards as Tolkowsky-derived round brilliants and there are less specific mathematical guidelines of angles which determine a well-cut stone.
Cuts are influenced heavily by fashion: The princess cut is also popular amongst diamond cutters: The past decades have seen the development of new diamond cuts, often based on a modification of an existing cut.
Some of these include extra facets. These newly developed cuts are viewed by many as more of an attempt at brand differentiation by diamond sellers, than actual improvements to the state of the art.
The quality of a diamond's cut is widely considered the most important of the four Cs in determining the beauty of a diamond; indeed, it is commonly acknowledged that a well-cut diamond can appear to be of greater carat weight, and have clarity and color appear to be of better grade than they actually are.
The skill with which a diamond is cut determines its ability to reflect and refract light. In addition to carrying the most importance to a diamond's quality as a gemstone, the cut is also the most difficult to quantitatively judge.
A number of factors, including proportion, polish, symmetry , and the relative angles of various facets, are determined by the quality of the cut and can affect the performance of a diamond.
A diamond with facets cut only a few degrees out of alignment can result in a poorly performing stone. For a round brilliant cut, there is a balance between "brilliance" and "fire".
When a diamond is cut for too much "fire", it looks like a cubic zirconia , which gives off much more "fire" than real diamond.
A well-executed round brilliant cut should reflect light upwards and make the diamond appear white when viewed from the top.
An inferior cut will produce a stone that appears dark at the center and in extreme cases the setting may be seen through the top of the diamond as shadows.
Several different theories on the "ideal" proportions of a diamond have been and continue to be advocated by various owners of patents on machines to view how well a diamond is cut.
These advocate a shift away from grading cut by the use of various angles and proportions toward measuring the performance of a cut stone.
A number of specially modified viewers and machines have been developed toward this end. Hearts and Arrows viewers test for the " hearts and arrows " characteristic pattern observable in stones exhibiting high symmetry and particular cut angles.
Closely related to Hearts and Arrows viewers is the ASET which tests for light leakage, light return, and proportions. Detractors, however, see these machines as marketing tools rather than scientific ones.
The GIA has developed a set of criteria for grading the cut of round brilliant stones that is now the standard in the diamond industry and is called Facetware.
The process of shaping a rough diamond into a polished gemstone is both an art and a science. The choice of cut is often decided by the original shape of the rough stone, location of the inclusions and flaws to be eliminated, the preservation of the weight, popularity of certain shapes amongst consumers and many other considerations.
Oddly shaped crystals such as macles are more likely to be cut in a fancy cut —that is, a cut other than the round brilliant—which the particular crystal shape lends itself to.
Since the per carat price of diamond shifts around key milestones such as 1. Some jewelry experts advise consumers to buy a 0. In the gem trade, the term light performance is used to describe how well a polished diamond will return light to the viewer.
There are three light properties which are described in relation to light performance: Brilliance refers to the white light reflections from the external and internal facet surfaces.
Fire refers to the spectral colors which are produced as a result of the diamond dispersing the white light. Scintillation refers to the small flashes of light that are seen when the diamond, light source or the viewer is moved.
A diamond that is cut and polished to produce a high level of these qualities is said to be high in light performance.
The setting diamonds are placed in also affect the performance of light through a diamond. The three most commonly used settings are: Prong, Bezel, and Channel.
Prong settings are the most popular setting for diamond jewelry. 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.
In bezel settings the diamond or gemstone is completely surrounded by a rim of metal, which can be molded into any shape to accommodate the stone.
Used to set earrings, necklaces, bracelets, and rings, bezel settings can have open or closed backs, and generally can be molded to allow a lot of light to pass through.
Channel settings set the stones right next to each other with no metal separating them. This setting is mostly used in wedding and anniversary bands.
The outer ridge is then worked over the edges of the stones to create a smooth exterior surface. This also protects the girdle area of the stone. 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.
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.
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. Since blue is a complementary color to yellow and can appear to cancel it out, strong blue fluorescence had especially better color appearance with lower color graded diamonds that have a slight yellowish tint such as I or J color but had little effect on the more colorless D, E and F color grades.
Cleanliness significantly affects a diamond's beauty. A clean diamond is more brilliant and fiery than the same diamond when it is "dirty".
Dirt or grease on the top of a diamond reduces its luster. Water, dirt, or grease on the bottom of a diamond interferes with the diamond's brilliance and fire.
Even a thin film absorbs some light that could have been reflected to the viewer. Colored dye or smudges can affect the perceived color of a diamond.
Historically, some jewelers' stones were misgraded because of smudges on the girdle, or dye on the culet. Current practice is to clean a diamond thoroughly before grading its color.
Maintaining a clean diamond can sometimes be difficult as jewelry settings can obstruct cleaning, and oils, grease, and other hydrophobic materials adhere well to a diamond.
Many jewelers use steam cleaners. Some jewelers provide their customers with ammonia -based cleaning kits; ultrasonic cleaners are also popular.
Historically, it has been claimed that diamonds possess several supernatural powers:. Because of their extraordinary physical properties , diamonds have been used symbolically since near the time of their first discovery.
Perhaps the earliest symbolic use of diamonds was as the eyes of Hindu devotional statues. Vajra is the word for diamond and ayudham means weapon in Sanskrit.
Another name for it was Agira which means fire or the sun. In fact there are 14 names counted to be given to a diamond in traditional Hinduism.
The oldest dated printed book in the world is called the Diamond Sutra , a Chinese text dating from and was found in the Mogao Caves.
Sutras are most used to describe the teachings of Buddha. In this case the title of the Sutra refers not to the diamond itself but to a 'diamond blade that will cut through worldly illusion to illuminate what is real and everlasting'.
Jewel imagery forms a central part of Buddhism: The book presently resides in the British Library. Many cultures use divine intervention to explain the origin and creation of gemstones, and diamonds were no exception to this.
In Greek mythology for example it was the youth on the island of Crete that disturbed Zeus and who were then as a form of punishment transformed into the adamas.
Philosophers however had a more naturalistic approach to explain the origin of gems: Plato for example believed gemstones were a consequence of fermentation in the stars, where a diamond actually formed the kernel of gold-bearing mass.
In later times, Robert Boyle actually believed that gems including a diamond were formed of clear, transparent water, and that their colors and characteristics were derived from their metallic spirit.
The diamond is the birthstone for people born in the month of April, and is also used as the symbol of a sixty-year anniversary , such as a Diamond Jubilee see hierarchy of precious substances.
In a system of heraldry by gemstone occasionally used in the past for the arms of nobles, diamond was used to represent the color sable, or black.
The origin of the 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 Romans valued the diamond entirely on account of the supernatural powers they ascribed to it. Pliny wrote that a diamond baffles poison, keeps off insanity, and dispels vain fears.
On this account it was recommended as the stone to be set in wedding or espousal rings—not on account of its beauty therefore, which was described by Isidore of Seville as a small stone devoid of beauty.
In more recent times a Parisian Oracle of mystic subjects, the Baron d'Orchamps, announced the diamond, if worn on the left hand warded off evil influences and attracted good fortune and since he had fashionable clients the word spread and the wearing of the diamond on the left hand became in itself a fashion.
One of the first occurrences of the diamond engagement or wedding ring can be traced back to the marriage of Maximilian I then Archduke of Austria to Mary of Burgundy in The popularity of the diamond ring as an engagement ring for a much wider audience can be traced directly to the marketing campaigns of De Beers , starting in In the early 20th century, a chairman of De Beers optimistically predicted that the diamond trade would prosper "so long as men are foolish and women are vain.
Today, the brilliant is still the most popular diamond shape for an engagement ring. About 70 percent of the sold diamonds are brilliants.
The increase in online sales are disrupting the market for diamonds by bringing greater transparency to an industry that has traditionally relied on opacity.
In some of the more politically unstable central African and west African countries, revolutionary groups have taken control of diamond mines , using proceeds from diamond sales to finance their operations.
Diamonds sold through this process are known as conflict diamonds or blood diamonds. Major diamond trading corporations continue to fund and fuel these conflicts by doing business with armed groups.
In response to public concerns that their diamond purchases were contributing to war and human rights abuses in central Africa and West Africa , the United Nations , the diamond industry and diamond-trading nations introduced the Kimberley Process in , which is aimed at ensuring that conflict diamonds do not become intermixed with the diamonds not controlled by such rebel groups, by providing documentation and certification of diamond exports from producing countries to ensure that the proceeds of sale are not being used to fund criminal or revolutionary activities.
This is a very stringent tracking system of diamonds and helps protect the 'conflict free' label of Canadian diamonds. From Wikipedia, the free encyclopedia.
Diamond mining in India. Big Hole and De Beers. Richards also discuss Pliny's referral in Book XXXVI, 54 of the stone of "Naxos" as being adamas , and which had long been used for cutting and polishing.
A chief product of Naxos has long been a high grade of amorphous corundum which was used as an abrasive. Richards, Ohio State University, , page They further discuss his referral to the adamas coming from the "east" through Armenian traders but they show this was actually based on an erroneous interpretation of Theophrastus.
Williams, Diamond Mines of South Africa, New York, BF Buck Company, argues that the stone named " adamas " by the Greek and further referred to by Pliny was most likely a sapphire since this was a much more abundant stone, even amongst traders in Asia, than diamond especially when used in the context of " adamas " being an ornamental stone and not used in an "industrial" context of engraving gems.
There seems to be a consensus over a large period of time that in fact the " adamas " was not a diamond, but mostly any type of corundum, several other minerals such as spinel were probably confused with diamonds as well; particularly because of a similarity in hardness and their availability in the Mediterranean area.
He describes diamonds being worn as long as years ago, recorded in ancient Hindu writings. George Frederick Kunz in 'A Curious Lore of Precious Stones' describes how a diamond in ancient times is worn on the forehead until the early 19th century this was a tradition believed to bring good luck.
Devotional statues is not specifically mentioned. Diamonds, Gold, and War: Archived from the original on The Autobiography of John Hays Hammond.
Antwerp World Diamond Center. How to Buy a Diamond: How to Buy Diamonds, Pearls, Colored The nature of diamonds. Handbook of carbon, graphite, diamond, and fullerenes: Retrieved March 1, An Encyclopaedia of Occultism.
Leipzig, Verlag von S. Precious Stones in Nature, Art and Literature. An Essay about the Origin and Virtue of Gems. Fire in the Earth, the Story of the Diamond.
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