Diamond - Information
What is a Diamond?
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What is a Diamond? This question had been unanswered till the end of the seventeenth century. Even the
relationship to carbon was suspected.
In 1694, two Italian academicians had done an experiment on diamond in Florence. They set up a large burning glass focused on a small diamond and saw it “cracked, coruscate and finally disappear”, leaving a minute quantity of blue ash. But it was the French physicist Babinet, who proved beyond reasonable doublet that a diamond was carbon in exceptionally pure form.
One of Lavoisier’s most celebrated experiments was to place a diamond in a bell jar filled with oxygen which rested in a basin containing mercury. The rays of the sun were then focused on the diamond by means of a large burning glass. After the diamond had been consumed, the bell jar was found to contain great quantities of carbonic acid, indicating to Lavoisier that the diamond was composed of carbon. Later experiments by Humphry Davy in England prompted him to conclude that the diamond was composed of carbon and nothing else, a view that was first contradicted in 1841 by Dumas and Strass whose numerous experiments revealed minute traces of other elements notably nitrogen and aluminum. It is these slight impurities that deform the perfect crystalline structure of the ideal diamond and can have a marked effect on the physical properties of a stone.
It would be an exaggeration to say that not much more is known about the origin of diamonds today, more than two thousand years ago when they were believed to be the splinters of stars. Nevertheless, it is true that there is still no unanimity among geologists about exactly how and where diamond is formed. As late as the nineteenth century, theories about the origin of diamonds had been shaped by the fact that the stones had always been found on or very close to the surface, either in riverbeds or in the beds of the rivers that had dried up ages ago. Even as late as 1869 the Gentlemen’s Magazine of London reported that a “continental experimentalist” had declared that the intense cold of stellar space disassociated and crystallized carbon from “masses of meteoric nature coursing through space” and caused diamonds to fall from the sky. The editor went on to comment that “the location of diamonds upon the earth agrees much better with the hypothesis of a sky source than an earth source” and that “those cope specimens now attracting so much attention are found on the surface of the ground only it is of no use to dig for them”, still the “continental experimentalist” may well have a point. Diamonds have been found in meteor craters at Novo Urei in south-eastern Russia and at Canyon Diablo in Arizona; although most scientists believe they were created by the heat and pressure of impact and not carried to earth in the meteors.
It was not until the discovery of the “dry diggings” at Kimberley in 1870, coupled with the determination of the miners to excavate every inch of their dearly bought claims that it became clear that diamonds came from below and not from above. It was also clear that diamond was invariably associated with one particular type of rock and that this rock was only to be found in clearly delineated areas. Since the rock and the diamonds persisted at depth, it was soon suggested that these “pipes” were volcanic in nature and that diamonds had been formed out of carbon under intense heat and pressure deep in the bowels of the earth. They had been forced toward the surface when those long extinct volcanoes had erupted millions of years ago. This strange diamond bearing rock, soon to be called Kimberlite was assumed to be nothing more than solidified lava. But as mining progressed at Kimberley it was discovered that the pipes were not great volcanic funnels plunging into the earth’s core.
A great deal has since been learned from the making of synthetic diamonds and perhaps the most widely accepted current theory is that since diamond forms at pressures and temperatures between 0.5 million pounds per square inch, the formation must have taken place at depths of at least 120 miles, chemical studies pointed to the ultra basic rock peridotite in its molten form as the most likely to have provided the right conditions for the creation of diamond from carbon. The molten of crystallization is assumed to have been long and slow and the theory goes that conditions remained stable for a considerable period as a result of the pressure of carbon dioxide gas below became too great, the balance was changed and the diamond bearing magma was driven explosively towards the surface. On the way, it picked up other rocks and minerals forming itself into the “geological plum pudding” that we now call Kimberlite, eventually erupting through the surface of the earth and solidifying.
History:
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The story of the diamond begins in a remote era the world’s history, lost in the mists of time. For untold ages the diamond lay hidden and unregarded within the earth, until man at last recognized it as the most precious of all nature’s creation and begins to use it for his own delight and benefit. We will probably never know exactly when the the first diamonds were discovered. But we do know that from ancient time until eighteenth century, India was the world’s sole supplier. Although it is impossible to locate the first discovery, there are very early documents that mention the diamond and perhaps explain why man showed such special interest in it. Many histories maintain that the diamond has been known since ancient times.
In Greek literature from very early datethe word adamas ( which eventually gave its name, via Latin adamus, adamantinus, to the diamond) is often used in sense very close to that of yahalom, being similarly associated with the idea of invincibility. The first known use of the word occurs in the works of the poet. Hesiod, who lived in the eighth century B.C. But nowhere in Hesiod, or in any other writing of that period, is the term applied to a diamond or any other precious stone. For some eight centuries the word adamas was applied exclusively to iron, to describe its unbreakable quality. Not until the first century A.D. was the word used as a noun, by that time, no doubt, designating a diamond. It appears as such in the celebrated Roman encyclopedia, the natural History of Pline the Elder.
India: The first Producer
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It is curious that in all the numerous, lengthy arguments among historians over the origin of diamonds, discussion nearly always centers on the countries that acquired the gems and never on the country that produce them. From ancient times until Brazil entered the picture in the eightieth century, India was the only significant diamond producing country. Until the twentieth century, source for the study of diamonds in India were largely unavailable. In 1905, however, an ancient Sanskrit manuscript was discovered, the Artha Sastra of Kautilya, which may be translated as “The Lesson of Profit”. This remarkable work is basic text providing invaluable detail of the economic and legal history of India in the fourth century B.C. Kautilya was the minister of King Chandragupta Maurya and had helped put him on the throne of the kingdom of Magdha. King Chandragupta, who ruled from about 320 to 298 B.C., was the founder of the Maurya dynasty and may be called the first emperor of India. We know of him also through the Greek Megasthenes, who lived at his court until the discovery of the Artha Sastra, in fact, Megasthenes was our sole source of information on this period. A careful reading of Kautliya’s treatise reveals unquestionably that not only were diamonds known in the fourth century B.C., but they were commodities in a very active trade, were subject to regular taxation and customs duties, and were one of the sources of the royal revenue.
Diamond Found:
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The first undoubted diamond were discovered in India and it was there that the first systematic diamond mining was carried on Jean Baptiste Tavernier, the celebrated French Jeweller and traveller in the East, recorded intensive mining going on in the 1660’s at Kollur near Golconda the legendary fortress city that lent its name to the entire mining area and served as the headquarters of the Indian diamond trade.
It was at Kollur that the most famous Indian diamond-The Kohinoor, The Great Moghal and The Regent are said to have been found. Another celebrated diamond mining area was further north at Panna and neighbouring villages in the province of Bundelkhand. It is a strange coincidence that the Brazilian diamonds were found just as the supply from India was running down, and that even the Brazilian deposits were nearly exhausted in their turn, huge supplies were discovered in South Africa. It had long been thought possible that diamonds would be found in South Africa. The early Boers were farmers not explorers and they had little interest in geology that not leads them to fertile soil or abundant water. It was not until thirty years later in 1866, that the first known diamond was picked up.
Everyone knew that diamonds came from India and more recently from Brazil and they had forgotten the skepticism that had greeted the Brazilian finds in the 18th century. The colonial secretary is to have taken the diamond into Cape town., placed his hand upon it and said “Gentlemen, this is the stone on which the future success of South Africa will be built.
Adamas: the Ancient Criteria Of Value:
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Why was it that people ascribed such value to the diamond before any technique had been invented to cut this “ king of precious stones ”? In the rough, most diamonds appear comparatively dull and unattractive. To find the answer to this question it is necessary to turn again to India, in the years between the beginning of the Maurya period in the fourth century B.C. and the end of the Gupta Period in the sixth century A.D. The Artha Sastra refers to a body of Oils and standards of practice developed by specialist to regularize taxes and other charges applied to diamonds and other precious stones.
Carbon Chemistry & Diamond Crystal Structure
The word 'diamond' derives from Greek adamao, meaning 'I tame' or 'I subdue' or the related word adamas, which means 'hardest steel' or 'hardest substance'. Everyone knows diamonds are hard and beautiful, but did you know a diamond could be the oldest material you might own? While the rock in which diamonds are found may be 50 to 1,600 million years old, the diamonds themselves are approximately 3.3 billion years old. This discrepancy is because the volcanic magma that solidifies into rock where diamonds are found did not create them, but only transported the diamonds from the Earth's mantle to the surface. Diamonds also may be formed under the high pressures and temperatures at the site of meteorite impacts. The diamonds formed during an impact may be relatively 'young', but some meteorites contain star dust, debris from the death of a star, which may include diamond crystals.
One such meteorite is known to contain tiny diamonds over 5 billion years old. These diamonds are older than our solar system!
Start with Carbon:
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Understanding the chemistry of a diamond requires a basic knowledge of the element carbon. A neutral carbon has 6 protons and 6 neutrons in its nucleus, balanced by 6 electrons. The electron shell configuration of carbon is 1s22s22p2. Carbon has af 4, since 4 electrons can be accepted to fill the 2p orbital. Diamond is made up of repeating units of car bon atoms joined to four other carbon atoms via the strongest chemical linkage, covalent bonds. Each carbon atom is in a rigid tetrahedral network where it is equidistant from its neighboring carbon atoms. The structural unit of diamond consists of 8 atoms, fundamentally arranged in a cube. This network is very stable and rigid, which is why diamonds are so very hard and have a high melting point.
Virtually all carbon on Earth comes from the stars. Studying the isotopic ratio of the carbon in a diamond makes it possible to trace the history of the carbon. For example, at the earth's surface the ratio of isotopes carbon-12 and carbon-13 is slightly different from that of star dust. Also, certain biological processes actively sort carbon isotopes according to mass, so the isotopic ratio of carbon that has been in living things is different from that of the Earth or the stars. Thus it is known that the carbon for most natural diamonds comes most recently from the mantle, but the carbon for a few diamonds is recycled carbon of microorganisms, formed into diamonds by the earth's crust via plate tectonics. Some minute diamonds that are generated by meteorites are from carbon available at the site of impact; some diamond crystals within meteorites are still fresh from the stars
Crystal Structure:
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The crystal structure of a diamond is a FCC lattice. Each carbon atom joins four other carbon atoms in regular tetrahedrons (triangular prisms). Based on the cubic form and its highly symmetrical arrangement of atoms, diamond crystals can develop into several different shapes, known as 'crystal habits'. The most common crystal habit is the eight-sided octahedron or diamond shape. Diamond crystals can also form cubes, dodecahedra, and combinations of these shapes. Except for two shape classes, these structures are manifestations of the cubic crystal system. One exception is the flat form called a macle, which is really a composite crystal, and the other exception is the class of etched crystals, which have rounded surfaces and may have elongated shapes. Real diamond crystals don't have completely smooth faces, but may have raised or indented triangular growths called 'trigons'. Diamonds have perfect cleavage in four different directions, meaning a diamond will separate neatly along thes e directions rather than break in a jagged manner. The lines of cleavage result from the diamond crystal having fewer chemical bonds along the plane of its octahedral face than in other directions. Diamond cutters take advantage of lines of cleavage to facet gemstones.
Graphite is only a few electron volts more stable than diamond, but the activation barrier for conversion requires almost as much energy as destroying the entire lattice and rebuilding it. Therefore, once diamond is formed, it will not reconvert back to graphite because the barrier is too high. Diamonds are said to be metastable, since they are kinetically rather than thermodynamically stable. Under the high pressure and temperature conditions needed to form diamond its form is actually more stable than graphite, and so over millions of years carbonaceous deposits may slowly crystallize into diamond.
Resources:
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Diamond is the hardest known natural material and the third-hardest known material after aggregated diamond nanorods and ultrahard fullerite. Its hardness and high dispersion of light make it useful for industrial applications and jewelry.
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, which also means they hold a polish extremely well and retain their lustre. About 130 million carats (26,000 kg) are mined annually, with a total value of nearly USD $9 billion. About 100,000 kg are synthesized annually.
The name diamond derives from the ancient Greek adamas (“invincible”). They have been treasured as gemstones since their use as religious icons in ancient India and usage in engraving tools also dates to early human history. Popularity of diamonds has risen since the 19th century because of increased supply, improved cutting and polishing techniques, growth in the world economy, and innovative and successful advertising campaigns. They are commonly judged by the “four Cs”: carat, clarity, color, and cut.
Roughly 49% of diamonds originate from central and southern Africa, although significant sources of the mineral have been discovered in Canada, India, Russia, Brazil, and Australia. They are mined from kimberlite and lamproite volcanic pipes, which brought to the surface the diamond crystals from deep in the Earth where the high pressure and temperature enables the formation of the crystals. The mining and distribution of natural diamonds are subjects of frequent controversy such as with concerns over the sale of conflict diamonds (aka blood diamonds) by African paramilitary groups.
Kimberley Diamonds finds pink diamond - The Age:
Kimberley Diamonds finds pink diamond The Age, Australia - 4 hours ago Kimberley Diamond Co NL has discovered the first pink diamond at its Ellendale project in Western Australia. The rare diamond weighs in at 1.58 carats and ...Kimberley Diamond says achieved record production at Ellendale in ... Forbes Kimberley Diamond Unearths First Pink Stone at Ellendale Diamonds. netall 7 news articles
From Mine to Market:
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Diamonds had been found on the banks of active rivers or in the beds of rivers that had dried up thousands of years before but all the sources were clearly alluvial. The methods adopted for the mining and recovery of diamonds were therefore simple and labour intensive. Tavernier provides us with a graphic account of the techniques of the great mine of Kollur in the Kingdom of Golconda in India around 1650.
The recovery process for the diamond bearing, South-West Africa follows much the same pattern as that for kimberlite from the inland pipe mines, and the diamonds which emerge are sent to the same place for sorting and valuing- the control sorting office of the Diamond Producers Association in Kimberley. There the diamonds are cleaned in acid, counted and weighed. Consignments from the different mine each being with separately.
First of all the crystals are separated into broad gem and industrial categories with color and clarity being the principal determining factor. There is obviously some overlap between the two groups and it is the balance of demand from the jewellery trade and industrial sources that determines whether the borderline cases should become gems or be consumed by industry. Roughly 80 percent of all diamonds produced fall into the industrial category. The industrials are dispatched to Johannesburg for further sorting and then marketing.
The gem crystals are sorted according to Carat (size), Cut (shape), Clarity (purity) and Color – called 4C’s. The next step is to sort the crystals into their basic shapes, stones which are unbroken crystals.
After the crystals are sorted into their two thousands or more classifications and valued, they are sold by the Diamond Producers Association (DPA) down the line to the Diamond Trading Company (DTC) and sent then to their sorting office in London. Here they are sorted into individual parcels which cut across a number of categories and then offered to diamond dealers and cutters at sales hold ten times a year known as the sights.
The Diamond Producers Association and the Diamond Trading Company together with the co-operative marketing unit known as the Central Saving Organisation (CSO) bring order and stability to the whole diamond industry. About 80% of the world’s diamond production is marketed through the CSO.
Diamond Mines: More information click here
Diamond Cutting:
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The first great name in European diamond cutting is Louis de Berquen. Certainly the first regular cut was the table cut. It was originated in India and one point into a table and the opposite point into a smaller table called the culet and then grinding the four ribs above the girdle to provide facets on the upper part the crown and the four below to form facets on the lower part, the pavilion.
Another cut that tended to follow the shape of the rough was the rose cut. Flat underneath the upper and convex part was covered in facets: twenty four for a Holland rose, eighteen to twenty for a Half Holland and six to eight for an Antwerp rose. There were many variations on the cut, largely depending on the shape of the rough. A Double Rose was a diamond faceted in a dome on both sides, the first use of which is attributed to Louis de Berquen, when he cut the Florentine for Charles the bold. Rounded stones were suitable for a bead cut and pear shaped ones would become pendeloques.
One of the earliest faceted cuts which marked a step toward the modern brilliant was the Mazarin cut named after Cardinal Mazarin of France in the mid seventeenth century. It was a cushion shaped cut with 17 facets above the girdle and 17 below but it still lost a great deal of light through the bottom and the sides. A later variation called the triple cut or the old mine cut was the immediate precursor of what we know as the modern brilliant.
The brilliant cut or round cut diamond is deservely popular as a result of its brilliance its regular shape and standardization and because most rough diamonds lend themselves to the cut with an average weight recovery of the order of 50 percent. But it is not the only cut. Approximately 2 percent of rough diamonds, because of their shape or flaws, cannot be cut into a round brilliant without an unacceptable loss of weight. It is these stones that are cut into the shapes known as marquise, pendeloques (pear shaped) oval, emerald, triangle & square cuts. As a group these are all classed as fancy cuts. The pendeloque is for and away the most rare. These cuts are more expensive than the ordinary round brilliant cut because their cost of manufacture is high but higher weight recovery should be more than compensate for this factor. The emerald cut is used for long rough diamonds and although weight recovery is above average at approximately 60 percent, the cut sells at upto 25% less than a round brilliant because its long parallel facets fail to show the same degree of brilliance.
Processes done on rough diamonds or gems:
There are five processes used in the creation of a polished gem from the rough:
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Cleaving- splitting a stone along the cleavage plane. The art of the cleaner has always been regarded as the greatest talent in the diamond cutting industry.
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Sawing- dividing a crystal by using a diamond saw. Clean regular octahedral are normally divided by sawing. The diamond cutter is said to “saw grain” that is he cuts in a non-cleaving direction.
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Bruting- shaping a diamond by removing part of it by rubbing against another diamond. The next step is to shape the sawn or cleaved stone into a circular outline. The result of this very skilled operation should be a diamond with a perfectly rounded girdle set exactly parallel to the table. The diamond used as a tool is usually itself a rough and will be bruted in its turn.
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Grinding or Blocking- making a flat surface by holding the crystal against a rotating wheel applied with diamond powder. First he grinds the table of the diamond and then a crown or bezel facet between the girdle and the table. The stone is then turned over and four pavilion facets are ground below the girdle. These eight facets are followed by four more on the crown and four more on the pavilion.
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Brillianteering or Polishing – Preparing the finished gem by a more refined application of grinding techniques. The brillianteerer completes the whole operation by adding the remaining forty facets. First he cuts eight star facets where the crown facets meet the table and then 16 girdle facets where they meet the girdle. Finally he cuts two long facets called halves into each of the pavilion facets. All the facets are then polished.
Diamond Shapes: More information click here
How to Valuate a Diamond:
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Today the fact is that very few people can distinguish between a good diamond and a bad one, they do not even know if what they are looking is a diamond at all or not. Cut, Colour, Clarity & Carat are four parameters to evaluate a Diamond known as “4 Cs”.
1) Cut:
The proportions and finish grade of a diamond establish the quality of the cut. A good finish grade testifies to the workmanship of the diamond polisher. It refers to the symmetry of the facets and their overall finish. The best cut diamonds also have the right proportions between the different parts of the diamond. If these proportions are not optimal, the fire and brilliancy of the diamond are affected, and undesirable visual effects might occur.
2) Colour:
The point of colour grading is to mark the degrees of grading from the whitest possible stone down to the yellowest which is still acceptable as being of gem quality. This is true when the diamond is viewed from the front and the eye confused by the spectrum colours. Lighting is vitally important, sunlight for example contains ultraviolet light which can cause the diamond being examined to fluorescence very slightly blue but enough to hide any tint of yellow.
3) Clarity:
Having ascertained a diamonds colour, the next step is to grade it according to clarity by assessing its degree of freedom from imperfections, clarity grading is more straight forward than colour grading, but arguable classifications can still arise. Inclusions are tiny crystals of other minerals that crystallized at same time as the diamond. The vast majority of diamonds have such inclusions, usually crystals of olivine and garnet.
4) Carat:
The weight of a diamond is measured in carats. There are 5 carats as equal to 1 gram (142 carats to the  ounce) and the carat is commonly divided into 100 cents (points). Diamonds of less than 1 carat in weight are known as pointers. A small portable chemical scale can be used to weigh diamonds to within a hundredth part of a carat. So many jewellers use electric balances.
What is 5th ‘C’? –5th ‘C’ is a Certificate. Another important thing to consider in purchasing or selling a diamond is the diamond certificate. It is a vital document that proves the authenticity and quality of the diamond being bought or sold. A highly trained diamond grader evaluates and specifies the attributes of the diamond. Most of the people don’t know 4‘C’s of diamonds. The Certificate provides genuine details of a diamond issued by any Neutral Organisation. Learn more … (link to lab page)
Valuation:
All 4C’s are taken into consideration at the time of diamond valuation. Diamond with good Cut, Colour, Clarity and Carat weight is the most critical factor in determining price. Apart from the scarcity of the bigger stones is that while fashion and local taste may effect the desirability of colour and the extreme rarity of the truly flawless diamond increases the demand for slightly less perfect stones, weight remains the only constant and easily calculable factor under the grading systems most commonly used today. There is one advantage in seeing a diamond in its setting and that is setting itself may provide a valuable due to the nature of the stone.
Diamond Trading:
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The diamond business has been redefined by branding and the fundamentals of advertising, public relations, and marketing - all of which are geared to the downstream retail and consumer jewelry markets with their unique customer segmentation features and demographics. Online access to the multiple brand environment of the diamond business including articles about Lev Leviev & Bulgari - May 2004, the Art of Marketing and Branding Diamonds, and The Case of the Missing Icon - De Beers LV.
Emerging Trends Downstream:
Emerging trends in the global diamond jewelry, fashion, and retailing sectors
Antwerp World Diamond Center:
Approximately 1,500 diamond offices are located in Antwerp on Hoveniersstraat, Schupstraat, Rijfstraat, and Pelikanstraat.
Natural Diamonds:
The cumulative effect of branding can already be calculated and determined. The next challenge facing the diamond business, trade, and industry is promoting the importance of and supporting the integrity of natural diamonds (and their sources of rough). Private companies, individual diamond exchanges, the DTC, and the World Federation of Diamond Bourses have already started to address the issue.
Brands:
Branded diamonds and jewelry are the hottest topics in the diamond trade today; hearts and arrows, ideal cuts, round brilliants, squares, fancy shapes, fancy colors, modified rounds and fancies, the Regent, Queen of Hearts, Hearts on Fire, the Lazare Diamond, the Leo Diamond, Dream, Prince, Nakshatra, PrincessPlus, Royal Asscher, Lily Cut, Crisscut, cushion cuts, Rand, Cushette, Zales, Princessa, Flanders, Sirius, Tsarina, Lucida, Elara, Tycoon, Escada, Ashoka, Vera Wang, the Regent, the Queen of Hearts, the Eighternity, the Web Cut, and the Radiant Star to name but a few.
Mumbai
India's Diamond Capital:
Hundreds of diamond offices are located in the general area of the Royal Opera House near the Roxy Cinema. Surat, is the major diamond manufacturing center.
Sightholders:
Branded diamonds and jewelry and other sightholder programs have the advantage of support from De Beers and the DTC including a new trademark, the forevermark program, the Diamond Promotion Service (DPS) worldwide, the Diamond Information Centers, J. W. Thompson, and many other added value features and services.
Jewelry Trade Shows:
The favorite venues for launching a new line of diamond set jewellery or a new branded diamond are the jewelry tradeshows worldwide, including the JCK, the JA New York, the Couture Show, Centurion, Diamonds by JCK, and shows in Las Vegas, Tucson, Mumbai, Tokyo, Bangkok, Basel, Hong Kong, and China.
Bourses:
Offices in diamond exchanges and cutting centers, worldwide including Hong Kong, Antwerp, Ramat Gan, New York, Tokyo, India (Mumbai and Surat), Israel, China, Canada, Russia, South Africa, Dubai, Shanghai, and Moscow trade in both rough and polished diamonds.
Israel Diamond
Exchange:
Approximately 1,200 diamond companies are located in the Shimshon, Maccabi, Noam, and the Diamond Tower buildings.Diamonds - Luxury Marketing
Advertising has increased in luxury, business, travel, bridal, fashion, and jewelry magazines including Elle, Maxim, Oprah, Town & Country, Vogue, W, Robb Report, InStyle, and Vanity Fair to name but a few. The bridal market (and the media devoted to it) is considered to be an easy entrance course into the world of branding and brands, because the curriculum stays the same and the class changes on a regular basis.
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