Beginner's Guide to Gemmology presents the profiles of the principal gem materials. This book discusses the interesting characteristics of gemstones as the growing consumer market jewelry resulted in increased sales of gem testing instruments. Organized into 12 chapters, this book begins with an overview of the development of the science of gemmology. This text then explains the fundamental qualities necessary in a gem, including color, hardness, specific gravity, crystallography, refractive index, pleochroism, critical angle, luminescence, and absorption spectra. Other chapters consider the o