2019年3月10日 Here are some interesting facts about corundum: Corundum is one of the hardest minerals in the world, with a Mohs hardness rating of 9 This makes it an ideal 2023年7月31日 corundum, naturally occurring aluminum oxide mineral (Al 2 O 3) that is, after diamond, the hardest known natural substance Corundum Aluminum Oxide, Gemstone, AbrasiveCorundum is a very hard, tough, and stable mineral For all practical purposes, it is the hardest mineral after Diamond, making it the second hardest mineral It is also unaffected by acid s and most environments Corundum: The mineral Corundum, Sapphire, Ruby info
2020年1月31日 Corundum is a hightemperature mineral that forms naturally by metamorphism of aluminarich rocks under amphibolite and granulite facies conditions, and at temperatures between 500° and Corundum Corundum is a crystalline form of aluminum oxide (Al2O3) with traces of iron, titanium and chromium It is a rockforming mineral It is one of the naturally transparent materials, but can have different colors when Corundum Minerals Education CoalitionCorundum is an aluminum oxide mineral of the oxides and hydroxides group, with structural formula Al2O3 The structure consists essentially of a dense arrangement of Corundum – Virtual Museum of Molecules and Minerals
Corundum Al2O3 Crystal Data: Hexagonal Point Group: 3 2/m Crystals hexagonal, prismatic or steeply dipyramidal, tabular, rhombohedral, rarely acicular, typically rough, to Corundum Photo by Robert Weldon/GIA Ruby and sapphire (usually blue, but also in every other color) have been the most important colored gemstones for several thousand years Originating historically in GIA Gem Project Corundum