The Chemistry, Properties and Tests of Precious Stones

"The Chemistry, Properties and Tests of Precious Stones" by John Mastin is a scientific publication written in the early 20th century. The book focuses on the analysis of precious stones, exploring their chemical composition, physical properties, and methods of testing and classification. Mastin aims to provide valuable insight not only to experts in mineralogy but also to the interested layperson. The opening of the work introduces the definition of what constitutes a precious stone, emphasizing the characteristics that distinguish them from other minerals. The author notes that the value of precious stones is influenced by factors such as their rarity and changing public perceptions. Mastin explains the significance of various physical properties—like hardness, transparency, color, and crystalline structure—in categorizing gems. He sets the stage for a detailed exploration of these themes, indicating that subsequent chapters will delve deeper into specific stones as well as the processes involved in their study and classification.