Diamond, The Brilliant Ice

Currently identified with love, diamonds are the gemstone of choice in engagement, wedding, and anniversary rings. Contrary to popular belief, we have not always given diamonds as love tokens. That custom results from modern marketing techniques, not ancient traditions.

Our ancestors mined diamonds, but didn't use them extensively. Diamonds' extreme hardness made them difficult to use in any way but their natural form, which resembles lifeless glass, and they weren't considered desirable gemstones.

Their fiery beauty was revealed in the 1700s, when gem cutters mastered faceting-cutting flat sides on a gemstone to enhance its brilliance. Diamonds quickly became the most popular gemstone, a position they still hold.

Those who believe in crystal magic assert that diamonds have protective powers and use them to drive away evil spirits and nightmares. They also claim that diamonds give wearers self-confidence, especially in matters concerning the opposite sex.

Diamonds are very hard-their name comes from the Greek word for invincible. They are not, however, indestructible. Diamonds are brittle, allowing them to chip or shatter easily. Because they are pure carbon, fire destroys them.

Common diamonds are transparent, or "white," leading to the nickname "ice." We value white diamonds for their lack of color. As with all other gemstones, tiny amounts of chemical impurities create colors. Red is the rarest of all colors in diamonds.

Except for the colored varieties, diamonds are plentiful. Diamonds are expensive only because people covet them, and because cartels control the market. The quality, and price, of diamonds are evaluated using the four c's: color, clarity, carat, and cut.

When buying a white diamond, place it against a white surface to detect color tinges. A truly colorless diamond will always cost more. Colored diamonds, known as "fancies," are valued according to the depth and intensity of their hues.

Few natural gemstones, including diamonds, are perfect. They may have bubbles, lines, or even other minerals embedded in them. Gemologists call these flaws, which are often invisible to the naked eye, "inclusions." Clarity is a measure of how much the inclusions interfere with the passage of light through the gem. The greater a diamond's clarity, the greater its cost.

Jewelers weigh diamonds by carats. Because larger sizes are rarer, a two-carat diamond will cost several times more than a one-carat diamond.

Cut refers to the quality of the faceting. Diamond-cutters generally cut 58 facets, the number that maximizes brilliance. Poorly-cut diamonds lack fire. An expert cut can overcome flaws in clarity and color. Many professionals regard cut as the most important of the four c's.

JUST FOR FUN Drill a small hole near the top of a dime and suspend the dime on a safety pin. Attach the pin to your clothing. When people ask what it is, tell them that it's your "dime-on-pin."