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Tsarstone collectors guide


An isometric mineral, representing a naturally occurring crystalline form of pure carbon polymorphous with graphite, chaoite, and lonsdaleite and being the hardest substance known. Found in volcanic neck, volcanic pipe, and alluvial deposits. Cut into various forms and shapes, when free from flaws. Sometimes fluorescent under ultraviolet light. There are two distinct types of diamond; Type I, to which the majority of stones belong, which exhibits complete absorption beyond 300 nm, and Type II, the rare transparent type, which transmits light down to 225 nm. Its high dispersion makes it valuable as a gemstone. Diamond is ready subject to cleavage. Polycrystalline mineral variety and is crushed and used as an abrasive powder in drilling and cutting such as carbonado boart, ballas.
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