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The name diamond is derived from the Greek word adamas (“invincible”), which was probably applied by the Greeks to any hard stone, such as corundum. The first distinct and undoubted reference to diamonds occurs in Roman literature of the 1st century AD
Diamonds consist of pure carbon compressed into a tight, isometric crystalline form. They are considered the hardest substance on the earth. Brilliant diamonds have a high index of refraction. Light entering a cut, or cleaved, crystal from the top, may also eventually exit from the top. This gives a false notion of internal sparkle. Coloured flashes of light occur in a fiery diamond when light is separated into colours. A Diamond is a mineral form of carbon, valued as a precious stone, and also used for various industrial purposes. Diamonds occur in various forms, including the diamond proper (a crystalline gemstone), bort - an imperfectly crystallized type of diamond, extremely hard, and dark in color, ballas - a compact, spherical mass of tiny diamond crystals of great hardness and toughness, and carbonado - sometimes called black diamond or carbon, is an opaque grayish or black form of diamond with no cleavage. Two important characteristics of the diamond is the index of refraction and the dispersion is higher for diamond than for any other natural, transparent, colorless stone. Other characteristics of the diamond add nothing to its appearance but are frequently useful in identifying the stone and in differentiating between true diamonds and imitations. Because diamonds are excellent conductors of heat, they are cold to the touch. Most diamonds are not good electrical conductors and become charged with positive electricity when rubbed. Genuine cut diamonds, unlike imitations, are transparent to X rays.
There is a Diamond Report for every diamond that has been through the Laboratory process. On the Report it gives the details of the diamond examined. The clarity, cut, colour and carat weight is provided on the Report. (the 4 C's). Fancy Colours Diamonds also occur in nature in shades of pink, blue, green, amber, or even red. These rarely occurring colors are referred to as fancies and are evaluated by a different set of color standards. These standards take into consideration various factors such as hue and saturation. The laboratory also issues reports on coloured stones, the reports are based on the well recognized ICSL System initiated in 1982, as published in the USA by the accredited Gemologist Association. Fluorescence Fluorescence is the effect whereby invisible ultraviolet light is transformed into visible light. The colour of the fluorescence is usually blue, but other colours are possible. Normal daylight contains a certain amount of UV light and therefore fluorescence can influence the colour of the stone. In the case of blue fluorescence the colour of the diamond shows lighter under a lighting containing UV rays (tube lamps, sunlight) and darker under lighting without UV rays.
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