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Corundum is a crystalline form of aluminium oxide (Al 2 O 3) typically containing traces of iron, titanium, vanadium, and chromium. [3] [4] It is a rock-forming mineral.It is a naturally transparent material, but can have different colors depending on the presence of transition metal impurities in its crystalline structure. [7]
Silicon carbide (SiC), also known as carborundum (/ ˌ k ɑːr b ə ˈ r ʌ n d əm /), is a hard chemical compound containing silicon and carbon. A wide bandgap semiconductor , it occurs in nature as the extremely rare mineral moissanite , but has been mass-produced as a powder and crystal since 1893 for use as an abrasive .
A lapidary is a text in verse or prose, often a whole book, that describes the physical properties and metaphysical virtues of precious and semi-precious stones, that is to say, a work on gemology. [1] It was frequently used as a medical textbook, since it also includes practical information about the supposed medical application of each stone ...
[15] [16] The alleged medicinal properties of precious stones, as well as other powers they were believed to hold, were collected in texts known as lapidaries, which remained popular in Medieval and Early Modern Europe until the 17th century. Across cultures, different stones can symbolize or provide aide for different things.
The Old English Lapidary, for instance, detailed the healing properties of stones, reflecting the belief that gemstones could cure illnesses and provide spiritual protection. Kitson argues that lapidaries in this period served a dual purpose: they were not only scientific texts that described natural phenomena but also moral and religious ...
Moissanite (/ ˈ m ɔɪ s ə ˌ n aɪ t /) [5] is naturally occurring silicon carbide and its various crystalline polymorphs.It has the chemical formula SiC and is a rare mineral, discovered by the French chemist Henri Moissan in 1893.
Artificial stones usually come in the form of a bonded abrasive composed of a ceramic such as silicon carbide (carborundum); aluminium oxide (corundum, also known as water stone or India stone); and CBN (cubic boron nitride). They provide more aggressive cutting action than natural stones, and are used for the middle stages of knife sharpening ...
Charmstone (charm-stone and charm stone), a stone or mineral artifact associated with various traditional cultures, including those of Scotland and the native cultures of California and the American southwest. Snakestones (also Serpentstones), fossilised ammonites were thought to be petrified coiled snakes, and were called snakestones.