"A Diamond is Forever"

• Frances Gerety, copywriter at N. W. Ayer & Son, the first advertising agency in the US.

When Mr. Gerety coined this slogan in 1947 for diamond distributing giant De Beers, he couldn't have dreamed that his words, like the object of its adulation, would become "forever". Such is the popularity of this amazing piece of advertising creativity that in 2000, Advertising Age magazine named "A Diamond Is Forever" the best advertising slogan of the twentieth century. The phrase has also been immortalized in the popular lexicon by the eponymous James Bond film "Diamonds are Forever". And rightly so. Unlike other items of value, a diamond does not rust, decompose or wither away. Originating in the deepest reaches of the Earth and forged by tremendous heat and pressure, a diamond is indeed forever.

The word "diamond" originates from the Greek "adamos", meaning "unbreakable". Indeed , diamonds are the hardest naturally-occurring substances. Basically made of carbon, the same material of which charcoal is composed of, diamonds are created over billions of years around 100 miles below the surface . Diamonds have relatively high optical dispersion (ability to disperse light of different colors) and refractive index (ability to bend light when it passes through) which result in the characteristic luster.

What makes a diamond so precious ? First , is its extreme rarity. On an average, 100 tons of rock have to be mined to extract 2 grams of diamonds. Second , is its extreme beauty . There are a few parameters to determine a diamonds value - the four Cs (carat, cut, color, and clarity), shape and fluorescence. A diamonds history also affects its price. Many of the most famous , and valuable, diamonds today are not necessarily large, but they are definitely of immense historical importance . Case in point: the Kohinoor and the Hope Diamond. Of course, there are some like the Cullinan, which are famous by dint of their sizes alone.

A carat is a unit of measurement equivalent to 200 mg or 0.007055 ounces. Besides diamonds, carats are also used to measure other precious stones and pearls. The word comes from the Greek word for the carob seed, historically used by jewelers as weights on scales for their reputed similarity in weights. The cut of a diamond is the style used when shaping a diamond for polishing. A well-cut diamond is especially luminous. The most common type is the round brilliant, followed by fancy cuts such as modified brilliants, step cuts, mixed cuts, and rose cuts.

A chemically pure diamond is completely transparent . Small amounts of impurities like boron and carbon often contribute to vivid colors like blue, yellow, pink, red, etc. Depending on the hue and intensity of a diamonds coloration, a diamonds color can either add to or subtract from its value. Out of all colored diamonds, the red ones are the rarest. The fourth parameter affecting the price of a diamond is clarity, the quality of its appearance considering internal characteristics called inclusions and surface defects called blemishes. More the clarity, higher the price, with the exceedingly rare "flawless" graded diamond fetching the highest price.

Now we come to the final factor determining price - history. Almost all of the costliest diamonds have fascinating histories - indeed the history of diamonds is the history of mankind. Right from ancient times in India where they were first discovered to modern times when diamonds can be created artificially, diamonds have been an integral part of human civilization. But even today, as centuries ago, nothing says "I love you" as eloquently as a diamond ring.