It gives you a nice range of hardness which will eliminate many potential minerals. Color-changing alexandrite is nature’s magic trick. COLOR. A mineral is homogenous, naturally occurring substance formed through geological processes that has a characteristic chemical composition, a highly ordered atomic structure and specific physical properties. Excellent refer-ence for beginning collectors with extended introductory sections and appendices, plus over 600 speci-mens described in detail and in color. Practice . Add to Library … Mineral identification is done by checking for certain mineral properties or characteristics. Volume is the amount of space an object takes up. Geology Dictionary. Ruby is the birthstone for July and Sapphire is the birthstone for September. WorldCat Home About WorldCat Help. [William F Kohland] Home. In the Mineral Identification Gizmo™, under Choose property to test, select Density 1. 2. Red in lamplight. It’s the color-change variety of the mineral, chrysoberyl. If your mineral does NOT scrape the penny, record the hardness as 2.5