![]() Some emery is a mix of corundum and other substances, and the mix is less abrasive, with an average Mohs hardness of 8.0. It is commonly used as an abrasive on everything from sandpaper to large machines used in machining metals, plastics, and wood. The name “corundum” is derived from the Tamil word Kurundam, or the Sanskrit word Kuruvinda.īecause of corundum’s hardness (pure corundum is defined to have 9.0 on the Mohs scale), it can scratch almost every other mineral. Rubies are red due to the presence of chromium, and sapphires exhibit a range of colors depending on what transition metal is present. A rare type of sapphire, padparadscha sapphire, is pink-orange. Corundum has two primary gem varieties, ruby and sapphire. These impurities are the presence of transition metals in the crystal structure of corundum. It is a naturally transparent material, but can have different colors when impurities are present. Erosion may cause Emery to crumble and form sand, which are sometimes called “black sands.”Ĭorundum is a crystalline form of aluminium oxide(Al2O3) typically containing traces of iron, titanium, vanadium and chromium. It is a rock-forming mineral. ![]() The industrial term “emery” describing Corundum abrasives is derived from the variety Emery which is mined specifically for its use as an abrasive. These are fairly common forms, and due to their great hardness and prevalence are the most favorable abrasives. Translucent brown Corundum and Emery are the most common forms of Corundum. It is also unaffected by acids and most environments. ![]() For all practical purposes, it is the hardest mineral after Diamond, making it the second hardest mineral. Sapphire is also only used to describe the gem variety otherwise it is simply called Corundum.Ĭorundum is a very hard, tough, and stablemineral. Ruby is the red variety, and Sapphire is the variety that encompasses all other colors, although the most popular and valued color of Sapphire is blue. Ruby and Sapphire are scientifically the same mineral, but just differ in color. Corundum is best known for its gem varieties, Ruby and Sapphire. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |