Gems; Notes and Extracts

Gems; Notes And Extracts by Augusto Castellani. Gems; Notes And Extracts is a nineteenth-century reference work on gems and minerals, translated from Italian by Mrs. John Brogden. The volume surveys mineralogy and gemology, outlining how minerals are classified and grouped, and then proceeds to describe a wide range of mineralogical gems—from common stones like agate, amethyst, and ruby to less familiar varieties such as adularia, aventurine, and jargoons. It explains fundamental properties of gemstones, including hardness, specific gravity, brightness, color, transparency, electricity, and fusion behavior, while also detailing historical uses, legends, and the perceived value of gems across cultures. The text blends scientific notes with historical anecdotes, engraving practices, and market considerations, presenting both practical lapidary information and context for gemstone collecting and study. It also includes a substantial Introduction and Epilogue providing a framework for understanding gem genera, orders, and their metalogical classification.