Three "faces" in sapphire

Today we will talk about three minerals, named after researchers, found in the form of inclusions in sapphire, important for its diagnosis and determination of the fact of heat treatment. Boehmite, which is found in the overwhelming majority of natural sapphires, should rightfully be called the first mineral. It was named in 1927 by Jacques de Lapparent (1883-1948) after the Austro-Czech chemist and crystallographer Johannes Böhm (1895-1952). The second mineral is goethite, which is also present in natural sapphires and is an excellent indicator of the heat treatment of stones. When sapphire is heated to temperatures at which the qualitative characteristics of color and purity change, goethite turns into hematite. The mineral was named in 1806 by Johann Georg Lenz (1748-1832) in honor of the German writer, philosopher and naturalist Johann Wolfgang von Goethe (1749-1832). And the third mineral is gibbsite, which is also found in natural sapphires in the form of microinclusions. The mineral was named in 1822 by the American biologist and mineralogist John Torrey (1796-1873) after the American naturalist George Gibbs (1776-1833).

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