corundum, sources.12, Myanmar (Burma).12, trapeche ruby, gems

Describes a ruby from Mong Hsu, Myanmar, displaying a segmented structure resembling that of trapiche emeralds. The boundaries separating the ruby sectors consist mainly of calcite and ankerite, interpreted as having been incorporated along the most rapidly growing crystal planes. Two colour photographs illustrate the unusual structure. The report also notes the recent discovery of a trapiche sapphire at Mong Hsu.

gems, inclusions, beryl, emerald, Madagascar

beryl, emerald, Pakistan, Swat, gems

Gübelin describes the discovery, geological setting, mining and processing of emeralds in Pakistan’s Swat Valley, particularly near Mingora. Emerald mineralisation occurs along shear zones and contacts involving talc-rich rocks, with associated quartz and carbonate veins. The author interprets their formation as the result of hydrothermal fluids acquiring chromium from ultrabasic rocks before depositing emeralds in favourable structural settings. Crystals enclosed in softer talc schists are better preserved than those in fractured quartz veins. The article also outlines open-pit extraction, sorting and cutting practices, noting that the finest stones combine strong green colour, transparency and brilliance comparable to Colombian emeralds.

gems, inclusions, beryl, emerald, Madagascar

corundum, Pakistan.12, gems, spinel

An illustrated survey of Pakistan’s gemstones that relates their properties and occurrence to the country’s geological and tectonic setting. An introductory section explains gemstone composition, physical properties, identification instruments, cutting and polishing, and the acquisition of rough. Subsequent chapters organize the deposits by geological association, covering emeralds associated with the Indus suture, ruby and spinel in the crystalline marbles of the Hunza region, pegmatite minerals, and gemstones from hydrothermal veins. Detailed accounts include aquamarine, tourmaline, feldspar, quartz, and topaz, with particular attention to the pink topaz of Katlang. Pakistani emeralds are also compared with synthetic material. Maps, geological sections, tables, and color photographs connect descriptions of individual gems with their host rocks and regional environments. Photographs by E.J.Gübelin illustrate inclusions, while A.H.Kazmi contributes specimen and landscape images. Brief concluding sections address miscellaneous gem materials and Pakistan’s gem market. Intended partly to encourage further discoveries, the book provides an accessible geological foundation for prospectors, gemologists, jewelers, and collectors, supported by an extensive bibliography.

corundum, history, India.12, gems, Indian lapidary

Silva examines the trade in precious stones in sixteenth-century Lisbon, when Portuguese maritime expansion made the city a major European entrepôt for gems arriving from India and other parts of Asia. Drawing on contemporary documentary sources, he discusses the importation, valuation and sale of diamonds, rubies, sapphires, emeralds, pearls and other precious materials, together with the merchants, jewelers and lapidaries involved in their distribution. The influx of eastern gems attracted foreign lapidaries to Lisbon and contributed to the development of a specialized gem and jewelry trade. The study also considers commercial practices, including the packaging and valuation of shipments and the role of foreign banking and mercantile houses, placing the gemstone trade within the broader economic consequences of Portuguese expansion in the Indian Ocean. Later work by Silva developed the subject in English as “The Portuguese Gem Trade in the Sixteenth Century” (Jewellery Studies, No. 6, 1993, pp. 19–28).

gems, beryl, emerald, inclusions, Brazil

synthetic beryl, emerald, gems

Describes and illustrates the identifying features of several newer synthetic emeralds. The first part examines Lennix synthetic emeralds, while the second discusses Biron emeralds and two Soviet products, one flux-grown and the other hydrothermally grown. The series presents diagnostic features useful in recognizing these laboratory-grown materials.

gems, early lapidaries, early gemology, early mineralogy, Marbode of Rennes

This thesis begins by an introduction which contains, the life of Marbode of Rennes, something about the history of lapidaries, above all of Latin lapidaries, and explains the contents of the liber lapidum. In the second chapter, the author enumerates the medieval translations of the book into eleven languages and describes the editions of the Latin text. The chapter ends with a list of the manuscripts of the liber lapidum kept outside of France and with a description of the history and of the contents of the manuscripts kept in France. In the third chapter, we have the classification into six families of the manuscripts kept in France. The thesis ends with a supplement containing two chapters of the critical edition that the author will publish in the future: the prologue and chapter vi on the emerald with a French translation. At the end we find a bibliography and an index of the manuscripts cited in the thesis.

beryl, synthetic beryl, emerald, synthetic corundum, gems

Gübelin reviews the diagnostic properties of several recently introduced synthetic gemstones and the problems they pose for separation from their natural counterparts. Emphasis is placed on the combination of conventional gemological properties with microscopic examination of inclusions and growth structures, supplemented where necessary by spectroscopic and other analytical methods. The article discusses characteristic features of newer synthetic materials, particularly synthetic corundum and emerald, and shows that physical constants alone may be insufficient for identification as manufacturing techniques increasingly reproduce the appearance and properties of natural stones. Gübelin stresses the diagnostic importance of flux residues, metallic inclusions, growth zoning and other internal features associated with particular synthesis processes. The paper summarizes practical criteria by which these newer products can be recognized in gemological testing.