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Waste Material from diamonds

Posted September 24th, 2008 by admin

Waste material from diamond cutting is used for industrial purposes, such as drills and polishing material. Diamond powder, which was originally the waste from the processes of cleaving and bruting crystals, was used only for grinding and polishing. But now it is considered to be the best abrasive on account of its great hardness and sharp edges. Suitable material is now crushed for this purpose. Faulty material discarded in the fashioning of other stones is mostly useless; a little corundum and garnet are used for polishing and drilling, chiefly in the East. All stones of appreciable worth are valued on the basis of weight, so not only must the best results be obtained from the rough stone in hand, but unnecessary loss of weight must be avoided.

Many stones which come from the East, such as Ceylon, India, and Siam, are cut in their country of origin. Such stones include jade, garnet, moonstone, ruby, sapphire, zircon, spinel, and chrys-oberyl. But in most instances, especially with the transparent stones, re-cutting is essential when they reach the West since the facets are generally unsymmetrical and their proportions wrong according to modern ideas. These so-called “native cut” stones are considered only with a view to retaining as much weight as possible, so although the color may be brought out, many of the imperfections within the stone are retained to its detriment. Jade is
an exception. This stone is almost exclusively cut in China, and the skill shown in working it, especially in the carving, far exceeds anything that has been done elsewhere.