John MastinJohn Mastin was a 19th-century British chemist and mineralogist who specialized in the study of gemstones. He is best known for his book, "The Chemistry, Properties, and Tests of Precious Stones," which remains a classic text in the field of gemology His book quickly became a standard reference for gemologists, jewelers, and anyone interested in the study and appreciation of precious stones. In addition to his work on gemstones, Mastin made contributions to the fields of metallurgy and chemistry. He was a member of the Royal Society of Arts and Sciences and the Society of Arts and Manufacturers, and he received numerous awards and honors for his work. Hereby, John Mastin was a respected expert in the science of gemstones and made significant contributions to the fields of chemistry, mineralogy, and metallurgy. His book on the chemistry, properties and tests of precious stones remains a valuable resource for gemologists and jewelry enthusiasts today. Read More Read Less