Expert Guides Minerals Gemstones Author:David C. Cook, Wendy L. Kirkt Features 300 minerals and gemstones, from copper, gold, and silver to opal, kernite, and gismondite ? Learn what the Earth is made of, how its rocks were formed and how minerals and gems are used today. ? Information tables give color, luster, streak, hardness, specific gravity, cleavage, habit, and crystal system ? Each entry is illustrated wit... more »h a full-color photo« less