Mineralogy classified into density (often given as specific gravity); measures of mechanical cohesion (hardness, tenacity, cleavage, fracture, parting); macroscopic visual properties (luster, color, streak, luminescence, diaphaneity); magnetic and electric properties; radioactivity and solubility in hydrogen chloride (). "Hardness" is determined by comparison with other minerals. In the Mohs scale, a standard set of minerals are numbered in order of increasing hardness from 1 (talc) to 10 (diamond). A harder mineral will scratch a softer, so an unknown mineral can be placed in this scale by which minerals it scratches and which scratch it. A few minerals such as calcite and kyanite
Mayo Mohs Mayo Mohs Mayo A. Mohs (March 23, 1934 – August 22, 1996) was the editor of the 1971 science fiction anthology "Other Worlds, Other Gods: Adventures in Religious Science Fiction" (Doubleday & Company, 1971, Library of Congress Catalog Card Number 76-144282.) Per the jacket of that book, "Mayo Mohs is religion editor of "Time" magazine and a long-time science fiction buff. The idea for this collection was originally inspired by an article he wrote for "Time" on theology and science fiction. A native of St. Paul, Minnesota, Mr. Mohs has been a history teacher and a reporter for the "Cincinnati