corundum, history.1, India.12, gems

Collot’s Le Corindon is a short French treatment of corundum based on T. H. Holland’s contemporary work on the mineral, particularly his revised Corundum section of the Manual of the Geology of India. It surveys corundum as a mineral species, including its physical and chemical properties, varieties, geological occurrence, geographical distribution, and economic uses. Particular attention is given to Indian deposits, where corundum occurs in numerous geological environments and had long been worked both as an abrasive and, in its transparent colored varieties, as ruby and sapphire. The work discusses the relationships between corundum and its enclosing rocks, its associated minerals, and the conditions under which deposits suitable for commercial exploitation occur. It also distinguishes ordinary industrial corundum from gem-quality material and summarizes information on mining and utilization. The booklet is essentially a concise French presentation of Holland’s more extensive study and reflects the increasing economic and geological interest in corundum at the end of the nineteenth century.