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.

beryl, emerald, Colombia, gems

gems, beryl, emerald, Zambia, Kitwe, Kafubu

gems, Islamic art, Islamic metalwork, Islamic jewelry, Islamic gems, ruby, diamond, spinel, emerald, jade

This was the first outline of Islamic Iranian metalwork to be published in any language. It is based on the collection in the Victoria & Albert Museum and is the work of Dr. Assadullah Souren Melikian-Chirvani [b. 1936], the distinguished authority of Near Eastern metalwork. The many illustrations present relevant details of epigraphy and iconography, the great majority of which have not been previously published. Souren Melikian is a French-Iranian art historian, art critic, and curator. He is a renowned scholar of Iranian culture, and its sphere of influence.

corundum, inclusions.5, diamond, beryl, emerald, spectroscopy, gems

Dele-Dubois, Dhamelincourt, and Schubnel examine the application of Raman spectroscopy to the non-destructive identification of mineral inclusions in diamonds, sapphires, and emeralds. The technique permits inclusions to be analyzed in situ through the host gemstone by means of their characteristic Raman spectra, avoiding the need to extract or otherwise damage them. The authors demonstrate the usefulness of Raman spectroscopy for identifying very small inclusions that may be difficult to determine by conventional microscopy, illustrating its value both for gemological identification and for investigating the mineral assemblages trapped during gemstone formation.

corundum, Australia.12, gems

The diamondiferous and the sapphire-zircon gemmiferous gravels of eastern Queensland and New South Wales are buried Tertiary fluvial clastics preserved from erosion by overlying basalt flows. The igneous sources of the gemmiferous fraction are unknown. The Great Artesian Basin (Cretaceous) across western New South Wales, Queensland, and northern South Australia hosts the continent's precious opal districts. Igneous and metamorphic host rocks for gemstone deposits are rare on the continent. Notable exceptions are the chrysoprase veins associated with serpentite belts of eastern Queensland and the emerald deposits in the Precambrian Shield of Western Australia.

beryl, emerald, Colombia, gems

gems, Arabic mineralogy, Persian gemology, history of gemology, Arabic gemology, al-Tamīmī, pearl,

Mineralogical and gemological extracts from the large Arabic treatise on medicine and medicaments, based on the Paris manuscript. Schönfeld notes that this pharmacopoeia is “one of many dealing with simple healing materials, which borrow from Greek pharmacopoeias, particularly those of Dioscorides and Galen.” Among its contents are a list of abbreviations, an index to the literature, a biography of al-Tamīmī, descriptions of the manuscripts, orthographic and stylistic peculiarities, a discussion of medicine and magic, and a heavily annotated translation accompanied by the Arabic text. In general, the two classes of stones found in this work are: (1) “eye-healers,” including antimony, pearl, zircon, emerald, carnelian, hematite, coral, lapis lazuli, jet, turquoise, and meerschaum, among others; and (2) personal protective devices incorporating diamond, malachite, bezoar, and other substances. Isis, Critical Bibliography, vol. 69, 1978, p. 64.

beryl, synthetic beryl, emerald, gems

Two techniques, flux and hydrothermal, have been used to grow emerald crystals, and various solvents have been employed. The lithium molybdate flux technique originated with Hautefeuille and Perrey in 1888 and was independently brought to feasibility by Nacken and at I.G.-Farben. This technique has proved to be commercially viable in the hands of Chatham and Gilson, who both perfected their processes independently of the Nacken and I.G.-Farben work, as well as of each other. Hydrothermal work culminated in the success of Flanigen and others at Linde, who found two acid mineralizers which gave satisfactory emerald growth; this process has not been commercially viable. Other crystal growth approaches of less significance are also discussed. Much confusion has existed because several flux techniques have in the past been misidentified as hydrothermal (there is, in fact, no evidence that even Nacken ever grew hydrothermal emerald) and some techniques claimed to produce crystals probably only yielded emerald glass, an inferior product. This account is based on original research, on an extensive literature search, as well as on many personal interviews. It is intended to clarify the confusing record as well as to present what is known about the current technology of gem emerald synthesis.