gems, gemology, jewelry, jewelry making, jewelry arts, specific gravity

This remarkable work, written by a Parisian jeweler and aimed at both the general public and members of the trade, contains a wealth of information reflecting the state of contemporary knowledge at the time. A.E. Farn, writing about the book in The Gemmologist, vol. 9, no. 8 (1964), pp. 261–262, considered it to be “very much in accord with today’s gemmological thinking” and later praised it as “a well-written, authoritative book, refreshingly tackled, very much in advance of its day.” Unfortunately, the author omits any biographical details—possibly, as Farn himself admits, because none could be found. The first volume offers a thorough exposition of the mining and metallurgy of gold, silver, and platinum as used in the jewelry arts, with detailed sections on alloys, alloying, refining, assaying, preparing solders, and other aspects of manufacturing. However, it is the second volume that holds primary interest for the gemologist. It begins with an extended treatise on practical gemology, including the use of balances for accurate specific gravity determinations—an aspect the author, Boue, deems extremely important for distinguishing between stones that may be confusingly similar in appearance and color. This is followed by a section on diamond mining, especially in Brazil, and general remarks on all classes of diamonds regardless of source. Other sections treat common gemstones, materials used by lapidaries such as powders, fluxes, and acids, and French laws regulating the activities of goldsmiths and jewelers. The engraved plates illustrate many subjects, including crystal forms, assay equipment, SG balances and accessories, styles of faceted and cabochon gems, diameters and weights of cut diamonds, values in currency, a table of specific gravities, pearl diameters versus grain weights and numbers per ounce, a sketch of a pearl shell, pearling dragline and net, magnets, a nautilus shell, and several views of the Regent diamond.