gems, gems general

A detailed review of gem production, mining, and discoveries in the United States and abroad during 1910. Sterrett records a substantial decline in U.S. precious-stone production, from $534,380 in 1909 to $295,797 in 1910, largely because of reduced output of tourmaline, turquoise, and chrysoprase. Particular attention is given to turquoise and the rapidly expanding use of variscite, with extensive descriptions of new deposits in Nevada and Utah, including their geology, mineralogy, color, and suitability for jewelry. Other American materials treated include agate and jasperized dinosaur bone from Colorado, amethyst deposits in North Carolina and Georgia, aquamarine and other beryls, opal, lapis lazuli, tourmaline, sapphire, and californite, a compact vesuvianite or garnet resembling jade and considered suitable as a substitute for nephrite or jadeite. Diamond sections discuss the Arkansas field, California placer diamonds, microscopic diamonds discovered in chromite-bearing peridotite in British Columbia, and the major South African mines. Sterrett also describes North Carolina emerald prospects, Montana sapphires, Burmese ruby, sapphire, and spinel production, and numerous newly reported gem localities. The report concludes with production statistics and U.S. import figures, noting a slight increase in precious-stone imports during 1910, particularly pearls and rough diamonds.

corundum, history.1, gems, Arabic mineralogy, early lapidaries

Wiedemann examines the values assigned to precious stones in medieval Islamic sources, drawing upon Arabic writings on mineralogy, commerce, and gemology. He discusses the prices and relative esteem of various gemstones, including ruby, emerald, sapphire, pearls, and other ornamental materials, and considers the factors affecting their valuation, such as color, quality, size, provenance, and rarity. The paper provides insight into Islamic knowledge of gemstones and the economic and cultural importance attached to them, preserving information from Arabic authors concerning the classification, appraisal, and trade of precious stones.

corundum, history.1, India.12, gems

Van Linschoten’s Itinerario is one of the most important early European accounts of the Portuguese maritime empire and Asian trade. Based largely on his residence at Goa from 1583 to 1588 and his travels and observations in the East, it describes the countries, peoples, ports, navigation, commerce, and commodities of the Portuguese Indies and adjoining regions. Of particular interest are references to the trade in precious stones and pearls, including diamonds, rubies, sapphires, emeralds, spinels, and other gems encountered in India and the wider Asian trading network. Linschoten records contemporary information on their sources, markets, qualities, and values, making the work an important primary source for the history of the gemstone trade in the late sixteenth century. This 1910 edition presents the Dutch text of Linschoten’s account of his voyage and experiences during 1579–1592.

gems, Arabic mineralogy, al-Biruni, early lapidaries

Wiedemann presents notes toward a history of mineralogical knowledge among Muslim scholars, drawing particularly on a Gotha manuscript containing material attributed to ʿAlī ibn Aidamur ibn ʿAlī al-Gildakī and on fragments of al-Kindī’s mineralogical writings preserved by later authors. [208–209] Al-Kindī’s work is described as containing what Wiedemann considers among the earliest Muslim accounts of minerals in this field, including observations on the value and properties of diamonds, pearls, and turquoise. Pearls are said to come from Muscat, with the finest occurring between the mouth and ear of the shellfish; turquoise is described as changing color with weather, being affected by musk and water, and damaged by oil or fat. [209] Al-Kindī divides gemstones (ǧauhar) into those derived from animals and those from the earth, and the latter into transparent and opaque varieties. Pearls belong to the animal group; transparent stones are divided into precious and non-precious classes, with the precious stones including diamond among those that cut, and hyacinth, zircon, and emerald among those that do not. Hyacinth is further divided into red, yellow, sky-blue, and white varieties, each with numerous shades, illustrating the highly developed discrimination of color nuances in the Oriental gem trade. Carnelian, amber, and onyx are included among lesser stones, while coral is classified with plants. [210] Wiedemann also records al-Gildakī’s observations on glass, including its ability to be colored and molded and its behavior when heated, and cites al-Muqaddasī on naturally greenish glass from the Persian desert. The article concludes with a discussion of amber, including its medicinal and talismanic uses and the names applied to it by Byzantine and Arabic writers. [211]

corundum, ruby, sapphire, Thailand.12, Cambodia.12, gems

Turpin’s History of the Kingdom of Siam, originally published in French in 1771 and here translated by B.O. Cartwright, presents an eighteenth-century European account of Siam from its early kings through the destruction of Ayutthaya and the rise of Phya Tak (Taksin). Drawing largely upon reports of Catholic missionaries and earlier European writers, it gives particular attention to the reign of King Narai, Constantine Phaulkon, Siam’s relations with France under Louis XIV, the Macassar revolt, the overthrow of Phaulkon and expulsion of the French, and subsequent persecution of Christians. The most important later sections describe Burmese invasions, the capture and destruction of Ayutthaya in 1767, the sufferings of its inhabitants and European residents, and the political fragmentation and recovery that followed under Phya Tak. The final chapters broaden into descriptions of Siam’s neighboring kingdoms and an argument for renewed French commercial involvement in the region. Of gemological interest are numerous contemporary statements on mineral resources and the precious-stone trade. Burma and Ava are described as producing exceptionally fine rubies and sapphires, while Pegu exported gold, silver and precious stones, with “rubies” used broadly to include topaz, sapphire, amethyst and other gems. Laos is said to possess a mine yielding rubies and emeralds, including a celebrated royal emerald reputedly the size of an orange; Cambodia is credited with amethyst, ruby, topaz, chrysolite, agate and bloodstone; and Siam itself is reported to contain agate, diamonds and pearls. The work is valuable both as a near-contemporary European narrative of the political upheavals that ended the Ayutthaya kingdom and as a record of eighteenth-century European beliefs concerning the geography, commerce and gem resources of mainland Southeast Asia.

gems, agate, quartz, chalcedony, Germany, Idar-Oberstein, history, lapidary, fashioning

A contemporary survey of Idar-Oberstein and its gemstone industry, describing the geographical setting, local geology, agate deposits and the historical development of the region’s lapidary trades. The article explains the occurrence of agate in volcanic rocks, noting chalcedony, opal and crystalline quartz as cavity fillings, and traces the growth of medieval agate cutting under the protection of the Oberstein authorities. It describes the emergence of specialized trades including agate miners, cutters, hollow grinders, stone sawyers and drillers, and discusses the decline of local rough supplies followed by the importation of large quantities of Brazilian agate and carnelian beginning in the nineteenth century. The account also documents the broadening of the industry to other gemstones such as ruby, sapphire, opal, tourmaline, topaz, emerald, aquamarine, zircon and garnet, together with the rise of jewelry and metalworking manufacture in Oberstein. Detailed sections describe traditional water-powered cutting mills, grinding positions, sawing, drilling, horizontal lapidary machines, stone coloring, gem engraving and cameo cutting, as well as the organization of imported rough into public auctions. Illustrated with views of Idar-Oberstein, the castles and Felsenkirche, cutting workshops, drilling and lapidary equipment, and preparations for Brazilian agate auctions, the article presents the district as a highly specialized and internationally important center of gemstone fashioning and trade.

corundum, ruby, sapphire, history.1, sources, gems

Kunz’s long-running annual chapters provide a contemporary record of the gemstone industry during the first third of the twentieth century, combining reports on new discoveries and mining developments with information on production, prices, trade, cutting, jewelry fashions, and notable individual gems. Although strongly focused on the United States, the series ranges widely across the major gem-producing regions of the world and follows developments in diamonds, ruby and sapphire, emerald, pearl, tourmaline, beryl, topaz, turquoise, garnet, quartz varieties, jade and other ornamental materials. Individual installments commonly describe particular mines and deposits, changes in output and commercial importance, newly reported localities, unusual crystals and exceptional cut stones, and advances in lapidary practice and gem treatment. The early reports document the rapid growth of the American jewelry and diamond-cutting industries and the increasing demand for colored stones; for 1905, for example, Kunz records unprecedented U.S. precious-stone imports and vigorous demand across the gem trade. he series is also valuable for preserving contemporary geological observations and production statistics, including detailed accounts of South African diamonds, Burmese rubies, Colombian emeralds and numerous American gem deposits. Taken as a whole, these chapters constitute an unusually rich year-by-year chronicle of the transition of gemology from a largely descriptive and commercial field into an increasingly scientific and international discipline, while documenting the changing geography, technology and economics of the world gemstone trade.

corundum, history.1, gems

The Agni Purana, (Sanskrit: अग्नि पुराण, Agni Purāṇa) is an English prose translation of one of the major Sanskrit Purāṇas and an encyclopedic compilation covering mythology, ritual, cosmology, medicine, architecture, statecraft, astronomy and numerous practical arts. Of particular gemological importance is the section on ratna-parīkṣā (“testing of gems”), which lists stones appropriate for royal use, including diamond, emerald, ruby, pearl, sapphire, lapis lazuli, crystal and several less readily identifiable materials. Good gems are characterized generally by internal lustre, purity and well-formed shape, while dull, cracked or included stones are rejected. Diamond is praised when pure, unbreakable, bright and exhibiting rainbow-like lustre; emerald should possess a parrot-green hue, gloss and radiance; rubies are classified partly according to their supposed sources and colors; and pearls are valued for roundness, whiteness, transparency and weight, with both naturalistic and legendary origins being recorded. Sapphire is described in terms of its strong color and lustre, while lapis lazuli is recommended for necklaces and other ornaments. The passage is valuable less as mineralogy in the modern sense than as evidence for early Indian systems of gem classification, quality assessment, auspiciousness and the close association of precious stones with kingship and personal fortune.

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

A comprehensive review of the precious-stone industry and important gemological developments during 1901, which Kunz describes as the most successful year yet in the history of the American trade. U.S. production was valued at $289,060, led by Montana sapphires, turquoise, rhodolite garnet, tourmaline, quartz, and other ornamental stones, while imports of diamonds and other precious stones reached about $22.8 million. Notable developments included a diamond from Lee County, Georgia; expanding sapphire mining at Yogo, Montana; an output of about 200,000 carats of rhodolite from Cowee Valley, North Carolina; colored tourmalines at Mesa Grande, California; chrysoprase near Visalia; new turquoise deposits in Colorado and Nevada and continued major production in New Mexico; large epidote crystals from Alaska; and a jade-like compact idocrase from California. Kunz gives detailed accounts of South African, Guianan, and Bornean diamond mining, Montana sapphire geology and recovery, American corundum deposits, the improving fortunes of the Burma Ruby Mines Company, emerald and beryl occurrences, garnet, quartz varieties, opal, turquoise, apatite, and other gem materials. He also discusses contemporary gem cutting and jewelry fashions and comments extensively on Chinese jade objects reaching Western markets following the looting associated with recent conflicts in China. The report concludes with statistical tables of U.S. precious-stone production from 1896–1901 and imports from 1867–1901.

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

Kunz reviews the precious-stone industry during 1899, combining accounts of American discoveries and production with developments in the international gem trade. Particular attention is given to diamonds, including discoveries in the United States, the South African diamond fields and industry, and production in Brazil, Australia, and other countries. He discusses corundum gems, including American sapphire and ruby occurrences, as well as emerald, beryl, chrysoberyl, garnet, tourmaline, turquoise, quartz, opal, and other gem and ornamental materials. The report records new or developing American localities, notable specimens, mining and cutting activity, production and import values, and contemporary changes in demand and fashion, providing a detailed picture of the American gem industry and its relationship to the international precious-stone market at the close of the nineteenth century.