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Tsarstone collectors guide


The quality of resistance or property of minerals, gemstones, etc., which is determined by reference to an empirical scale of standard of minerals. Hardness is the resistance of a mineral offered to abrasion or scratching (scelerometric). The absolute hardness is determined with the aid of a sclerometer. Hardness varies according to crystallographic direction in certain minerals, such as cyanite or disthene three different hardness in three different crystallographic directions: 4.5, 6, and 7. The hardness of a gemstone can be determined using a hardness plate or hardness points. The general scale used as standard by mineralogist and gemologist called MohsТ scale.
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