gems, gemology,

Chudoba and Gübelin provide a compact practical reference to gemology intended both for identifying gemstones and for standardizing the often confusing terminology used in the German gem trade. The principal gemstones and ornamental materials are arranged alphabetically and characterized by their chemical, crystallographic, and physical properties, important localities, trade names, and diagnostic features. Separate sections treat inclusions in natural gemstones, synthetic stones, doublets and triplets; tables of gemological constants; coated stones; synthetic gems and other imitations; the gemological microscope; and practical identification tables. Particular emphasis is placed on simple tests that can be performed with readily available gemological instruments and on microscopic inclusions as a means of distinguishing natural stones from synthetics and assembled or imitation materials. Conceived as a concise working handbook rather than a comprehensive mineralogical treatise, it became the basis for the substantially enlarged second edition of 1966, retitled Edelsteinkundliches Handbuch, and a further expanded third edition in 1974.