The first riverbed diamonds, the birthstone of April, were presumably discovered in India around 800 B.C. India was the major source of diamonds until 1975 when diamonds were discovered in Brazil. South Africa’s massive diamond deposits were found in 1866 and with it came the worldwide diamond rush. It was not until the Siberian permafrost in 1954 that the South African diamond output met its rival. Western Canada is currently the site of the world’s newest diamond rush.
Fancy-colour diamonds are natural, rare and truly exotic gems of the earth. Diamonds in hues of yellow, red, pink, blue, and green range in intensity from faint to vivid and generally the more saturated the colour, the higher the value. Diamonds sparkling with intense colour are rare and may be priced higher than a colourless diamond of equal size. Colour is sometimes introduced in a laboratory to achieve the desired shade. These are correctly called colour-treated diamonds. When purchasing a fancy-colour diamond, be sure to ask if any enhancements or treatments were used to improve its colour and/or clarity.
The Four Cs: Carat weight, colour, clarity and cut are the characteristics that alone determine the price and quality of a diamond.
Carat: The carat weight measures the mass of a diamond. One carat is defined as exactly 200 milligrams (about 0.007 ounce). The value of a diamond increases exponentially in relation to carat weight, since larger diamonds are both rare and more desirable for gemstones.
Colour: Diamonds are graded for colour on a scale of “D” or colourless, to “Z” or dark yellow. A chemically pure and structurally perfect diamond is completely transparent with no hue or colour. Almost no gem-sized natural diamonds are absolutely perfect. The colour of the diamond may be affected by chemical impurities and structural defects in the crystal lattice. The hue and intensity of a diamond’s colouration can enhance or detract from its value.
Clarity: Flaws inside a diamond are commonly referred to as inclusions. These imperfections may be crystals of a foreign material, another diamond crystal or structural imperfections (tiny cracks that can appear whitish or cloudy). The number, size, colour, relative location, orientation and visibility of the inclusions can all influence the clarity of a diamond.
Cut: The cut of a diamond describes the manner in which a diamond has been shaped and polished from its beginning form as a rough stone to its final gem proportions. The cut describes both the shape a diamond is formed into as well as the quality of workmanship. Round or brilliant is a favourite among engagement rings. Emerald cut is rectangular in shape with facets polished diagonally across the corners. Marquise or pointed boat shape is long and narrow and tends to slim the finger. Pear shape is popular in rings as well as pendants. An adaptation of the brilliant shape, oval tends to appear larger than a brilliant of the same carat weight.
* image courtesy the American Gem Trade Association (AGTA)