Mohs hardness Profile: TECHNO/HOUSE/ROCK VJ ”Despite its simplicity and lack of precision, the Mohs scale is highly relevant for field geologists, who use the scale to roughly identify minerals using scratch kits. The Mohs scale hardness of minerals can be commonly found in reference sheets. Reference materials may be expected to have a uniform Mohs hardness.” http://www.ijcbht.com/ https://iflyer.tv/ja/artist/48474/