Diamonds in the Rough

They Are Forever and a Girl's Best Friend; Here Is How to Tell the Gems from the Junk
| By Ettagale Blauer | From Tom Selleck, Winter 95/96

It was the end of the workday at the diamond sorting house in Kimberley, South Africa. The sorters, weary from a day of peering at piles of rough diamonds, made their way out through the tight security of Harry Oppenheimer House into the brilliant late-day sun. One sorter walked briskly to her car, making sure she didn't get caught up in a friendly chat that might have ended in a handshake. She would have had a hard time shaking hands--hers were closed around handfuls of rough diamonds, taken from the millions of carats that pass through the sorting house each year. She didn't come back to work the next day; and she was never caught.

It was one of the simplest and most successful diamond heists ever pulled off, and the man telling me the story knew his stuff. He was Brigadier Henrick Erasmus, retired head of the diamond squad of the South African police department. He spent his entire career chasing down diamond thieves.

Diamonds are the stuff that dreams, songs and thrillers are made of. They are elusive and expensive bits of glittering brilliance, a girl's best friend, precious and rare. They lurk under vast deserts, or lie buried within ocean beds or locked within rock so hard they must be blasted loose in mines a mile beneath the earth's surface.

Yet diamonds are more numerous than most people think. They do lurk beneath tons of sand and they are dynamited out of rock, but they are not rare. The diamonds that glitter in jewelry showcases and on a woman's fingers and earlobes, at her neck and occasionally in her nose, are mined by the millions of carats, and there are more millions taken from the earth every year. If they were truly rare, they would not form the center stone of three-quarters of the engagement rings sold in the United States.

So if they're not rare, why are they so expensive? Did someone repeal the law of supply and demand?

The primary explanation is De Beers, a name synonymous with diamonds. All the mystique, all the myth and a good deal of the reality of diamonds today evolve around De Beers. While this 107-year-old South African company's grip on the marketing of diamonds has slipped a bit during the past decade, it still has the power to beckon the world's diamond merchants to its London office to buy its diamonds in person--at De Beers' schedule, at De Beers' prices. No quibbling. No bargaining.

Every five weeks, approximately 150 wholesale diamond buyers arrive at De Beers' offices, where they are taken to individual rooms and presented with a plain cardboard box, about the size of a shoe box. Inside, neatly folded in the white tissue papers used throughout the diamond world, the dealers find rough diamonds in an assortment of sizes and qualities, chosen for them by De Beers. They are told the price, and that's the deal. Since De Beers maintains control over the marketing of an estimated 80 percent of the world's newly mined diamonds, the buyer pays up. Only "specials," diamonds above 10 carats, allow for negotiation in price.

De Beers' control of the market has been attacked on a number of fronts over the years, but the most serious threat to its monopoly came with the demise of the Soviet Union. Russia is not only a major diamond mining region, but it is also sitting on a huge stockpile of diamonds. It's no secret that the country is strapped for cash; the quick sale of a lot of diamonds would be a way of helping Russia out of that dilemma. The problem is that flooding the market with diamonds would immediately cause prices to drop; the Russians would diminish the value of their own stockpile. So, although diamonds continue to dribble out of Russia, De Beers and its chairman, Harry Oppenheimer, have been able to maintain pretty tight control.

Diamond is the hardest mineral on earth, so much harder than the next closest mineral (corundum) that it cannot be depicted to scale on a hardness chart. Yet diamond is simply crystalline carbon that has been subjected to tremendous heat and pressure, forming in volcanic pipes and found in igneous formations called kimberlites. After surviving this violent birth, the diamond waits beneath the earth's surface for millions of years.

Geologists follow telltale signs to locate diamond pipes; it may take 20 years of dogged, nose-to-the-ground searching to find one, but it's worth the effort. New finds such as Jwaneng in Botswana and Venetia in South Africa are worked as open-cast strip mines: Ore is blasted loose from sections of the mine; huge terraces, wide enough for big dumpsters to drive around and pick up the ore, are worked in increasingly smaller, concentric circles. When the working surface gets too deep for this method to continue, it becomes necessary to sink a mine shaft and begin underground work.

The difficulty of wresting the diamond from the earth is matched by the challenge of transforming it into a faceted gem. The diamond's brilliance is hidden until facets have been cut, allowing light to enter the stone and bounce back to the eye. It is this quality of refraction that makes diamonds appealing to the eye. But a diamond must possess two characteristics in abundance in order to refract the most light: It should be relatively free from inclusions (foreign matter within the diamond) and it must be shaped, or polished, according to a precise mathematical formula.

These are two of the four qualities known popularly as the "Four C's": color, clarity, cut and carat weight. Color and clarity are closely related; both depend on the degree to which other minerals were present when the diamond was formed. The best diamonds are colorless, or nearly so, with the fewest traces of other minerals. The more transparent the stone, the better it can refract light. This is where the issue of true rarity comes into play, for although diamonds are found in abundance, the clearest, purest diamonds are truly rare.

If the supply of diamonds may be thought of as a pyramid, the base is occupied by small, flawed diamonds of poor color. The farther up the pyramid, the better the color and the fewer the flaws. Near the top are diamonds of the finest color and clarity; there are fewer of these and fewer still that possess these qualities as well as great size or carat weight. The pinnacle is occupied by the once-in-a-lifetime perfect diamond of enormous size. The best color is "D," on the most commonly used evaluating scale of D (colorless) to Z (visibly yellow); the best clarity is "flawless"; size can be 100 carats or more. There are only a handful of such enormous, perfect stones, and a scant number of buyers around the world who are willing and able to buy them.

Diamonds increase in price geometrically as they increase in size. Simply put, a two-carat diamond costs more than twice as much as a one-carat diamond because it is rarer, and so on up the weight scale. While there are standard benchmark prices for diamonds of small size or weight, diamonds weighing more than 10 carats are priced individually. The way the diamond has been polished or shaped becomes progressively more important as the size increases. A tiny mistake in a tiny diamond has little impact, but it becomes magnified in a bigger gemstone; just think of the Hubble Space Telescope with its tiny error in lens polishing.

If a diamond is the hardest mineral known, what could possibly be used to cut it? Only another diamond. Let's abandon the term "cut" when we speak of shaping a diamond. Diamonds are polished on a wheel that is coated with a mixture of oil and diamond dust. The abrasive quality of the diamond dust does the polishing. The diamond is set into a "dop," a device that holds the stone and exposes the portion to be polished. This face of the stone is polished against the wheel until it is flat and smooth; this is called faceting. The position of the stone is changed in the dop and the next facet is polished, and so it goes, from one side to the other, top to bottom.

The diamond polisher works by eye, with the image of the finished stone in his mind. Methodically, he polishes the diamond until 58 facets have been created, meeting at angles, next to each other, one on top of the other. The more precisely he places each facet, the more brilliantly the stone will refract light.

If the uncut diamond, or rough, is to be cut into a round stone, also called a "brilliant," the 58-facet formula applies, whatever the weight of the diamond. But diamonds are fashioned into other shapes, such as pear, rectangular (also called emerald-cut), square, triangular, oval and heart shapes, as well as the marquise, an oval that is pointed at both ends. The facets of these stones are polished according to different patterns. The rectangular and square cuts are polished in steps, much like a flight of stairs. They do not refract light as a round cut does but have a cool beauty of their own. Large diamonds may be shaped with more than 58 facets, giving greater visual interest to the stone. These trademark cuts include the "Radiant," the "Quadrillion" and the "Trilliant."

If a diamond is forever, how can a diamond cutter possibly cleave one? Diamond, being a natural substance, has a grain. By studying the stone, the cutter finds the grain and plans his attack accordingly. If he places his tiny chisel in exactly the right place and taps it just so, the diamond obligingly splits into two parts.

Why would he want to do this if a large diamond is more valuable than a small one? The answer is found in the typical shape of diamond rough, called an octahedron. By cleaving an octahedron, the cutter is left with two diamonds that are roughly the ideal shape: a pyramid topped by a small trapezoid. The 58-facet plan fits ideally on this basic shape, allowing the cutter to retain as much weight as possible while achieving the best cut. Even so, the polishing process usually reduces the weight of the diamond by about half.

Cleaving is also employed when an enormous piece of rough contains some deeply flawed sections. By lopping off these sections, a stone of better quality and considerably more value emerges, even though the weight has been reduced. Sometimes a rough is so huge it cannot be fashioned into a wearable or usable single stone. Such was the case with the Cullinan diamond, found at the historic Premier Mine in South Africa in 1905. This 3,106-carat rough, weighing about one and a half pounds, was cut into nine major gems and 96 smaller stones. The largest, a 530.20 carat pear-shape, was named the "Great Star of Africa." You can see it if you visit the Tower Museum in London, for it is part of the British Crown Jewels.

If a diamond can be split deliberately, it follows that it can also be cleaved inadvertently. If a stone is hit hard, at a cleavage plane, it can split. Though rare, this does happen, proving that not every diamond is forever.

Tiny rectangular stones called baguettes are frequently used to enhance a central diamond or to highlight jewelry set with colored gemstones. When baguettes are used in a curved setting, they are tapered at one end to conform to the setting. Though small, these precisely cut stones add considerably to the cost of the jewelry because of the skilled labor involved in cutting them.

Setting techniques give the jewelry designer a wide range of design images. Drawing upon these different methods, the designer can create a variety of styles, from the casual to the formal, the traditional to the contemporary. The classic engagement ring diamond is set within slender prongs, usually made of platinum. A row of diamonds may be set side by side in a channel of metal for a sophisticated look.

To stun the eye with glitter, designers create "pavé" settings, placing diamonds next to one another with a minimal amount of metal. Finely made pavé is extremely costly; each stone is set by hand, and though each one may weigh only a fraction of a carat, the labor costs are considerable. A pavé design may be set with hundreds of small, faceted diamonds. In the best work, the top facets of the diamonds are placed at slightly graduating angles to catch the light as the piece of jewelry is turned. This is a costly technique: Each tiny stone may cost $4 to set; a necklace set with 600 tiny diamonds has a $2,400 investment in the pavé setting alone. Add the cost of the diamonds and the gold, plus the designer's time, and the price for diamond-set jewelry starts to add up.

The difference between fine pavé work and ordinary pavé may be seen at a glance. Fine work is planned so the stones nestle together with almost no metal showing between them; the tiniest variations in stone size may be used to achieve this. Ordinary work is done in straight rows, with same-size stones; the subtlety of the setting is lost.

While colorless is the finest quality for a "white" diamond, there is a range of naturally colored diamonds that are valued quite differently. Called "fancy" colors in the trade, these diamonds have discernible body color that derives from other minerals that were trapped when the diamonds were formed. Of the fancies, yellow and cognac are the most common, followed by pink; blue and green stones are very rare. Fancy color diamonds have a beauty all their own, but the very presence of the minerals that give them their hue also detracts from their brilliance. Beauty in this case is very much a matter of taste.

Large fancy diamonds, like large colorless diamonds, are individually priced. Some of the best-known diamonds in the world are fancies: The 128.51 carat Tiffany Diamond is a bright canary yellow and the Hope Diamond is a deep blue. Tiffany has held onto its namesake stone, but the Hope Diamond, a "bad luck" 45.52 carat stone (according to legend bad luck follows its wearer), was bought by the flamboyant diamond merchant Harry Winston, who donated it to the Smithsonian Institution in 1958.

Diamonds, like fingerprints, are never identical and may be "fingerprinted" by means of a photo ID. This shows the pattern of inclusions within the diamonds, unique to each stone. The technique is not practical for very small diamonds and is confined to larger, more valuable diamonds; it must be done when the stone is unmounted. The ID of the diamond cannot be changed merely by polishing away a bit of weight, because it is the interior of the diamond that is being identified.

But diamonds are also identifiable, as a group, in terms of their origin. Diamantaires--true diamond experts--can usually tell if a diamond was mined in Russia, Botswana or Australia, three of the principal sources. While diamond marketing is the province of De Beers, diamond mining is much more widely dispersed. More gem-quality diamonds are mined in Botswana than in neighboring South Africa; more diamonds in total are mined in Australia than in any other country, although the great majority are of industrial quality, not suitable for use in jewelry.

Industrial diamonds (used for cutting tools and abrasives) differ only in the color and number of inclusions; industrial users would prefer gem diamonds (if they could afford them) because they last longer. Most mines produce a mix of industrial and gem diamonds, with industrials making up as much as 80 percent of the output. But some mines, such as the Beachfront operation in Namibia, produce nearly all gem-quality stones. Whatever the operation, huge amounts of earth must be removed to reveal the diamond-bearing ore beneath. A very good yield is roughly 100 carats of diamonds for each 100 tons of earth that is processed.

Diamonds continue to fascinate and delight with their combination of hardness and delicate appearance. These condensed bits of carbon will be at the center of many a mystery, but nothing can compare to the true story of the way a diamond is taken from the earth, polished and turned into a scintillating, wearable treasure.

Ettagale Blauer has written on diamonds for Cosmopolitan, Modern Bride, and the Rapaport Diamond Report, and is the author of Contemporary American Jewelry Design.

Shopping Around

Although diamonds aren't rare, each diamond is unique. They're devilishly hard to mine, tough to cut and expensive to set. How does that help you buy a piece of diamond-set jewelry?

In diamond buying, as in much of life, if a deal sounds too good to be true, it usually is. The diamond you may be offered in John Doe's shop is not the same as the diamond you just saw in Sam Roe's shop. Even if they're close in size, color and clarity, no one can compare two diamonds unless they're viewed side by side.

CARAT WEIGHT: Diamond weight is not approximate--it is exact. Each carat is divided into 100 points. The difference in price between a diamond that's exactly one carat and one that weighs 98 points is substantial. We like round numbers, and one carat is a round number. Each of those points counts toward the purchase price. A cutter will work hard to preserve the weight of a diamond during polishing to come up with that one carat or one carat-plus stone, instead of one that weighs 99 points. Five diamonds, each of 20 points, may total one carat in weight, but those five taken together are not as valuable as a one-carat diamond--remember, rarity.

COLOR: The whiter (more colorless) the diamond, the higher the price. The color of a diamond is graded on a letter scale of D to Z, with D being the whitest. Your eye (especially if you are a man) will likely not discern the difference in color between a "D" and an "F" color diamond, but put the "F" next to an "I" color and even those of the male gender may start to notice the difference. The comment about men is a fact; women are far better at seeing subtle color differences than men. But don't believe me; ask the folks in the sorting area at Harry Winston. The color sorters tend to be women; men sort for clarity.

CUT: The shape of a diamond is a matter of personal choice. Because round diamonds are the most common, this has become the accepted shape. The piece of rough usually dictates the shape. The cutter will turn a naturally elongated rough into a rectangle; rough with a narrow end will become a pear shape; rough that is naturally pointed at both ends becomes a marquise.

CLARITY: A diamond that has no visible inclusions when viewed under 10-power magnification is termed "flawless." Visible inclusions get lower gradings, ranging downward from "very slightly imperfect" to "imperfect." The higher the clarity rating, the higher the price.

MAKE: This is a trade term referring to the proportions of the stone. It is possible to produce a stone with the standard number of facets but without much brilliance. This may occur if the rough was relatively flat; the resulting polished diamond may be shallow and not have enough inner space to allow for the desired play of light.

Taken in total, this mix of qualities yields the price of a diamond. The compromises the diamond buyer makes when considering these variables depend very much on personal values: Whether size is more important than clarity, or clarity is more valuable than color, your eye is your ultimate guide.

CERTIFICATES: Diamonds are graded by laboratories according to their color, clarity, cut and carat weight. One of the most reputable labs is the Gemological Institute of America, with U.S. offices in New York City and Santa Monica, California. A GIA certificate does not include price information, but pinpoints a given stone's precise quality. GIA does not say "this is a good diamond"; it simply describes the diamond at hand.

APPRAISALS: When you buy a diamond, the receipt should include such basic information as carat weight, color and clarity. This is not an appraisal. An independent appraisal should be done by someone other than the seller. With the appraisal, you can have the piece of jewelry insured; the appraisal should be for its replacement value. If the appraised value is dramatically different from the price you paid, you should question the method used by the appraiser to reach the price given.

WHOLESALE: There may be someone in your life who can "get it for you wholesale." This is very tempting, since the markup on jewelry is usually 100 percent--or higher. But be wary of such offers. You may have little choice in the goods offered, you may feel pressured to buy something because a friend is involved and you may find it hard to return the purchase should the appraised value make it seem like much less of a bargain. True wholesalers prefer to deal with wholesale buyers, not individuals. Anyone who has a stream of people like you going in and out of his office is not selling wholesale--he's selling retail in an upstairs location.