gems, gems general

A comprehensive review of precious-stone production, mining, discoveries, and trade during 1909. Sterrett records a marked increase in U.S. gem production, especially turquoise, variscite, tourmaline, and chrysoprase, reflecting the growing popularity of blue and green matrix stones; more than 17 tons of rough turquoise and 3½ tons of variscite were mined during the year. A major portion of the report is devoted to detailed descriptions of American deposits, including turquoise and variscite in Nevada and Utah, a new emerald occurrence near Shelby, North Carolina, Montana sapphires, California tourmaline and californite, and numerous agate, amethyst, beryl, opal, garnet, and ornamental-stone localities. Particularly important is an extensive account of the newly discovered benitoite deposit in San Benito County, California, covering its geology, paragenesis with natrolite and neptunite, crystallography, optical properties, cutting, and gem qualities. The report also describes the newly named rose-colored beryl morganite from Madagascar. Diamond sections survey Arkansas, California, South Africa, German Southwest Africa, British Guiana, and Australia, while Burmese ruby mining at Mogok and sapphire production in Queensland and Ceylon are also discussed. The report concludes with U.S. production statistics and notes a strong recovery in precious-stone imports, especially rough and cut diamonds, indicating a return of the diamond trade toward pre-1908 conditions.

corundum, synthetic corundum.7, Verneuil, gems

Boyer’s original publication on gem materials synthesis precedes Michel’s Die künstlichen Edelsteine, 1914, which see, although the latter is far more thorough. The first German edition rewrote Boyer’s work into more easily understandable prose, included more historical data, gave fuller accounts of contemporary work in Germany, and otherwise substantially enlarged and improved Boyer’s edition. The present edition further enlarges the work. In general, major remarks are confined to the synthesis of corundum but also include comments on synthetic quartz, opal, emerald, and diamond, the German editors believing that diamond was actually made by Moissan. Amplifying remarks in part four discuss color in natural gemstones, distinctions between synthetic and natural gemstones, properties of synthetic diamond (!) and including their combustion, and prices of synthetic stones. Other parts treat impact of synthetics in industry and controversy over nomenclature and possible deceptive sales practices, and rather out of place, the cultured pearl.

gems, jade, pyroxene jade, fei cui, Mesoamerica, Guatemala, Mexico, Aztec, Olmec, opal, pearl, turquoise, agate

Kunz presents a broad survey of the gem and ornamental-stone resources of Mexico, combining contemporary mineralogical information with extensive discussion of pre-Columbian lapidary materials and their possible sources. He notes that opal was then the only gemstone systematically mined in Mexico and tecali, the so-called Mexican onyx but actually a form of banded aragonite, the principal ornamental stone. Other materials discussed include garnet, topaz, amethyst, rock crystal, chalcedony, agate, jasper, turquoise, obsidian, and reported but generally unsubstantiated occurrences of diamond, ruby, sapphire, and emerald. Particular attention is devoted to Mexican opal, including deposits in Querétaro, Hidalgo, Guerrero, Michoacán, Jalisco, and San Luis Potosí, their geology and mining, varieties and colors, cutting and commerce, and the tendency of some material to crack or lose its play-of-color as it dries. Kunz also describes the recently discovered turquoise occurrence near Bonanza, Zacatecas, and reviews the extensive use of turquoise mosaic in Aztec objects. A substantial portion of the work concerns chalchihuitl, which he recognizes as a general indigenous designation embracing several valued green materials rather than a single mineral. He distinguishes turquoise from what he terms the “precious chalchihuitl,” identified as jadeite, and discusses jadeite artifacts, archaeological discoveries, historical tribute records, and attempts to reconstruct the geographic sources of the material. Kunz states that jadeite, rather than nephrite, characterizes the Mexican and Central American jades known to him and argues from Aztec tribute records that its sources lay south of Mexico City, particularly toward the Oaxaca–Veracruz border, Chiapas, and Central America. He nevertheless acknowledges that the primary deposits remained unknown and that much of the ancient material appears to have been obtained as stream-worn pebbles and boulders. The work is therefore both an early mineralogical survey of Mexican gemstones and an important historical treatment of the identification, use, archaeological distribution, and unresolved provenance of Mesoamerican jade and other greenstones.

corundum, history.1, curious lore, gems

A wide-ranging compilation of historical, folkloric, medical and occult beliefs concerning the curative powers of gemstones and the nobler metals. Fernie gathers material from classical authors, medieval lapidaries, early medical writers, folklore, literature and contemporary sources, discussing the supposed therapeutic virtues of individual stones and the diseases they were believed to prevent or cure when worn, carried, powdered or otherwise administered. Separate treatments include diamond, ruby, sapphire, emerald, amethyst, agate, bloodstone, coral, pearl, turquoise, opal, lapis lazuli and many other materials, together with gold, silver and related substances. The work is less a scientific mineralogical study than an extensive survey of traditional gem medicine, amuletic practice and popular belief, frequently juxtaposing ancient claims with modern medical commentary. Its chief value to gemology lies in the extraordinary breadth of historical lore assembled on the medicinal and supernatural uses of gems and in documenting the persistence of such beliefs into the early twentieth century.

corundum, history.1, Burma.12, India.12, Sri Lanka.12, Asia, Thailand.12, gems, Gasparo Balbi

An important early account of Burma by the Venetian jeweller Gasparo Balbi, who travelled east from Aleppo beginning in 1579 and reached Pegu in 1583. Balbi describes his route through the eastern Mediterranean, Persian Gulf, India and Southeast Asia, but the greatest value of the narrative lies in his observations on Pegu and the Burmese court. As a jeweller, he is of particular gemological interest: he carried emeralds from Venice and presented them to the King of Pegu during a formal audience, describing the elaborate court ceremonial surrounding the gift. He also records the extraordinary royal wealth of Pegu in gold, silver and jewels, together with its temples, gilded monuments, commerce, customs and political life. Purchas elsewhere summarizes Balbi as regarding the king of Pegu as among the richest rulers in the world in gold, silver and jewels. Although Balbi gives less direct information on Burmese ruby mining than some near-contemporary travellers, his account is especially valuable as the observations of a professional jeweller visiting the region at the height of the sixteenth-century Pegu trade, and as one of the earliest European firsthand descriptions of the Burmese court and its use of precious stones. He brought emeralds from Venice to trade for rubies, but also mentioned a good trade was bringing enamel bracelets in Saint Thomas for sale in Pegu.

corundum, USA.12, North Carolina.12, Montana.12, gems, Mineral Resources of the United States

Some of the salient features of the year are the finding of rock crystal at Mokelumne Hill, California, of such purity and size as to almost rival the Japanese, and the successful cutting of these in the United States up to 7 inches in diameter; the increased output of Fergus County, Montana, sapphire mines, and the yielding of fine blue gems up to 2 carats each, and the discovery of a new locality where the stones are more varied in color than those of any known locality; the continued output of the New Mexican turquoise mines and the opening up of mines in Nevada; the finding of magnificent green and other colored tourmalines at Paris Hill, Maine, and Haddam Neck, Connecticut; the increased sale of Australian opal; greater use of all the fancy or semiprecious stones; the greater importation of uncut diamonds, and the increase of the diamond-cutting industry in the United States; the unprecedented increase in the importation of cut diamonds; the revival of the precious stone industry in the United States, and the positive great future advance in the price of pearls and emeralds, and the advance in the price of diamonds.

gems, Egypt, Egyptian history, Egyption, Sudan, emerald mines, gold mining, Nubia

Floyer reports the results of the scientific expedition dispatched by the Khedive to examine the Northern Etbai, some 23,000 square miles of mountainous Eastern Desert between the Nile and Red Sea. The paper describes the geography, geology, antiquities, ancient mining remains, routes, water sources, and mineral resources encountered by the expedition, with particular attention to the celebrated ancient Egyptian emerald workings. Floyer describes emerald occurring in mica schist and identifies the most important workings around Wadi Sikait, where extensive ancient excavations and settlements testified to mining on a considerable scale; the emerald district was estimated to extend over some 40 square miles of valleys and mountains. The expedition was important in bringing renewed attention to the long-abandoned Sikait–Zabara emerald region, the classical Mons Smaragdus, and Floyer’s observations provide a significant late nineteenth-century record of the geology and physical condition of the ancient workings before modern investigation. The paper is illustrated with a map and was originally accompanied by water-colour drawings and photographs made during the expedition; an abridged geological account appeared the same year in the Quarterly Journal of the Geological Society.

corundum, ruby, Afghanistan.12, emerald, beryl, gems, spinel

Griesbach gives a brief geological account of the Safed Koh (Spin Ghar) range on the northwestern frontier of British India, describing the principal rock formations observed in the region and their structural relationships. The note records the geological character of this mountainous belt and places its formations within the broader stratigraphy of the adjoining Afghan frontier, drawing on observations made during Griesbach’s geological work in Afghanistan and neighboring territories. Although extremely brief, the notice contributes to the early Geological Survey of India documentation of the geology of the Safed Koh and the poorly known country between Afghanistan and the Indian frontier. Reports on occurrence of ruby and spinel at Jagdallak [Jegdalek]; he also mentions emerald.

corundum, Cambodia.12, Thailand.12, gems

Regional account containing a detailed description of the gem industry at Payrinh (Pailin), pp. 10–12. Brien estimates 3,000–4,000 miners, predominantly Burmese and Peguans known as Koulahs, and describes abundant but often pale sapphires and rarer, finer rubies, alongside stones identified as white topaz and emerald. He records trade through Chantaboun, Battambang, Phnom Penh, Bangkok and India; local cutting with sapphire powder; and final polishing with rice-husk ash on copper. Particularly significant is his description of red or dark-blue wax placed beneath pale stones in their settings to improve their apparent colour. He also discusses cabochon rings, the concealment of valuable gems beneath the skin during transport, abandoned gold workings at Ba Méas, and regional rock crystal occurrences.

corundum, history.1, gems

A wide-ranging historical and literary survey of precious stones by William Jones, concerned principally with their folklore, symbolism and cultural associations rather than their mineralogy. Jones examines ancient and medieval beliefs concerning the supernatural and medicinal virtues of gems, biblical and rabbinical traditions, planetary and birth stones, talismans, famous jewels, literary references, royal and ecclesiastical treasures, and the use of precious stones in crowns, regalia, jewelry and costume. Drawing extensively on classical, medieval and early modern authors, inventories, chronicles and poetry, the work assembles numerous accounts of diamonds, rubies, sapphires, emeralds, pearls and other gems and traces the legends and historical events associated with them. Jones explicitly states that he does not attempt to cover the mineralogical composition or structure of gemstones. The book is particularly valuable as a nineteenth-century compilation of gem folklore, historical jewelry references and literary traditions surrounding precious stones.