corundum, USA.12, North Carolina.12, Montana.12, gems

Kunz reviews the production, occurrence, mining, and trade of precious stones during 1892, with particular attention to developments in the United States. He records American gem production and discusses diamonds and a wide range of colored and ornamental stones, including sapphire, turquoise, tourmaline, garnet, beryl, quartz, opal, and other materials. The turquoise deposits of the southwestern United States receive specific attention [763–764], while the report also describes contemporary American sapphire occurrences and other newly developed or investigated gem localities. A substantial section is devoted to diamonds, including American occurrences and developments in the South African industry, with discussion of diamond-bearing rocks, mining, production, and contemporary ideas concerning diamond genesis. As in Kunz’s earlier annual reports, economic information is combined with mineralogical and gemological observations, making the paper an important contemporary record of the rapidly developing American gem industry and of the international precious-stone trade at the end of the nineteenth century.