gems, Brazil, diamond, topaz, gold, beryl, emerald, tourmaline, quartz, amethyst, Minas Gerais

Sinkankas: An outstanding and carefully researched work reflecting the author’s many years of practical experience in Brazil and involvement in the country’s mining industry. Although primarily concerned with gold, it contains an important section on gemstones (Part IV, pp. 345–446), covering diamonds, tourmaline, topaz, beryl, chrysoberyl, amethyst, euclase and other stones. It is among the earliest major works to provide a history of diamond and gemstone discoveries in Brazil, including the expeditions prompted by reports of emeralds, the subsequent discovery of diamonds, and the identification of supposed emeralds—reported from 1573 or earlier—as green tourmaline. It also describes Portuguese Crown regulations governing diamond mining and trade, reviews the diamond industry from 1749 to 1822 with production statistics, and discusses mining districts, administration, mining methods, diamond occurrences and crystal forms, specimens from the Serro do Frio in the Royal Cabinet, and the smuggling of gold and diamonds. A fundamental source for the history of Brazilian gold, diamond and gemstone mining.