Rough diamonds are diamonds in their natural state, as they were removed from the depths of the earth and prior to undergoing the polishing process which lends the stone the glitter and luster that characterize diamonds in the eyes of the general public.
To the uneducated eye, rough diamonds look more like shards of glass washed up on the beach: They are oily and dull, and come in colors ranging from yellow through green to brown. Their price is lower than that of Polished Diamonds. In order to bring out the rough diamond’s breathtaking beauty, a professional polisher must first cut and polish the stone.
Only 20% of the diamonds produced annually are designated as gem-quality. Most of them are of inferior quality and are defined as industrial diamonds. For the most part, when speaking of rough diamonds we are referring to those stones defined as gem-quality diamonds.
The criteria used to examine Polished Diamonds and determine their price – such as cutting and polishing – do not apply to rough stones. Rough diamonds are sorted into groups according to the crystals’ shapes, sizes and colors. Nevertheless, there is no regulated set of criteria to evaluate them, so it is difficult to assess their price.