travel & exploration, Asia, India, gems

A scholarly edition of the medieval travel narrative attributed to Sir John Mandeville, bringing together several textual versions for comparison. Volume I presents the Egerton text in modernized English, preceded by Letts’s introduction and an essay by E.G.R.Taylor on medieval cosmographical ideas. Volume II contains the French Paris text with an English translation, the shorter Bodleian version, and supplementary passages from German and Latin versions and related sources. The narrative moves from pilgrimage routes and sacred sites in the Holy Land to accounts of distant Asian kingdoms, combining geographical information, descriptions of customs and religions, and fabulous peoples and natural wonders. For gemological history, it preserves influential traditions concerning precious stones, notably diamonds said to grow, reproduce, and derive nourishment from heavenly dew, together with beliefs in their protective powers. Such passages document medieval lapidary lore and European perceptions of Asian wealth. The edition’s comparative texts and historical apparatus make it useful for studying how geographical knowledge, borrowed accounts, religious traditions, and marvels were assembled and transmitted.

jade, jadeite, fei cui, Maya, Guatemala, Aztecs, gems

Barber examines the evidence for indigenous jade supplies in Mexico and argues that renewed commercial demand could encourage the rediscovery of their sources. He describes a trade in which rural inhabitants sell ancient carvings unearthed during cultivation to intermediaries who supply urban dealers and tourist shops. The limited availability of authentic objects, combined with visitors’ interest in ornamental stones rather than archaeological authenticity, has encouraged the sale of substitutes, including green glass marketed as Mexican jade. Barber suggests that a dependable market for newly collected material could stimulate prospecting and support a revived carving industry, particularly if country people were assured of payment for suitable stones found in streams and elsewhere. Distinguishing nephrite from fei cui, he identifies the latter as the principal material of ancient Mexican jade carvings, while reporting that some objects are nephrite. He challenges theories that American jade was imported from Asia or that similarities between carvings demonstrate an Asian origin for indigenous American cultures. His argument rests on reported chemical and optical differences between the jadeite mineral in Burmese and American materials, especially the greater calcium and magnesium components attributed to the latter, which he interprets as evidence for an American source. The archaeological distribution of jade extends from Sonora to Panama, with particularly abundant finds in Guerrero, Oaxaca, Chiapas, Veracruz, and Tabasco; however, Barber cautions that this distribution need not indicate numerous deposits, since exchange and the widespread esteem accorded jade could explain its dispersal. For Maya communities in the limestone country of Yucatán, he proposes supplies from the mountains of Oaxaca or Guatemala, obtained through southern and western neighbours. He illustrates jade’s importance through protective and medicinal amulets, funerary practices involving stones placed in the mouth and images deposited with the dead, traditions surrounding Quetzalcoatl, and Aztec tribute records specifying jade objects and their places of origin. Ancient exploitation, he argues, need not have involved recognizable bedrock quarries: river pebbles and boulders may have furnished much of the material, an interpretation supported by carvings whose outlines accommodate the original stone’s shape. Rough boulders reportedly recovered from Maya temple ruins, including one weighing approximately 200 pounds, and a reported river find from the eastern Oaxaca highlands provide further indications of raw material procurement. Throughout, Barber connects the archaeological question of jade supply with the practical economics of collecting, emphasizing that local knowledge and financial incentives would be central to locating workable material.

corundum, Sri Lanka.12, inclusions.5, gems

At a meeting of the Mineralogical Society held on 24ᵗʰ January, 1952, for the second time within a year a new gem mineral was described. On the former occasion only two small cut specimens of the mineral (taaffeite) were on view, these representing the whole of the world’s known supply; whereas in describing sinhalite Dr. G. F. Claringbull was able to produce a score of cut examples, some of them of considerable size. There was also one small pebble of rough, recovered by Dr. E. H. Rutland from samples of illam held by the lapidaries, Charles Mathews & Son.

bibliography, book collecting, books on books, gems

John Carter’s ABC for Book Collectors, first published in 1952, is an authoritative and often witty dictionary of the specialized terminology employed by antiquarian booksellers, bibliographers, auctioneers, and collectors of rare books. Drawing upon Carter’s extensive experience in the antiquarian book trade, the work was designed to explain the technical language and conventions encountered in booksellers’ catalogues and auction descriptions, particularly those that might confuse newcomers to book collecting. Rather than offering a general history of printing or an encyclopedia of bibliography, Carter concentrates on the vocabulary necessary to understand, identify, describe, evaluate, and purchase collectible books. Arranged alphabetically, the entries explain terms relating to editions, impressions, issues, states, bindings, paper, typography, illustration, provenance, condition, rarity, and bibliographical description. Particular attention is devoted to the frequently misunderstood distinctions between first editions, first impressions, and subsequent issues or states, together with the evidence necessary to establish their chronological priority. Carter also examines the identification of incomplete, altered, restored, or otherwise imperfect copies, explaining such terms as cancels, collation, conjugate leaves, inserted advertisements, facsimiles, and made-up copies. The extensive treatment of bookbinding encompasses historical materials and techniques, including calf, morocco, vellum, buckram, publisher’s cloth, decorative tooling, and the various forms of contemporary and later bindings. Equally useful are the discussions of condition and the subjective language employed by booksellers, from descriptions such as “fine” and “very good” to euphemisms that may conceal serious defects. Carter warns collectors against exaggerated claims of rarity, unsupported assertions of priority, misleading bibliographical descriptions, and the temptation to equate high prices with importance. His observations on auction practices, provenance, association copies, presentation copies, dust jackets, and the preservation of original bindings demonstrate a practical understanding of the factors influencing the desirability and commercial value of books. Throughout the work, technical definitions are accompanied by historical examples, occasional anecdotes, and pointed comments on the habits and pretensions of collectors and dealers. The book’s distinctive combination of scholarship, practical advice, and dry humor distinguishes it from more conventional bibliographical dictionaries. Following Carter’s death in 1975, Nicolas Barker revised and expanded the work, incorporating developments in bibliography, the antiquarian trade, and collecting practices while preserving much of the original author’s distinctive style. Although the book contains no substantive gemological information, it is particularly valuable to collectors of historical gemological literature, providing the terminology and bibliographical principles needed to distinguish original editions from later printings, recognize significant variants, evaluate the completeness and condition of rare volumes, and interpret antiquarian booksellers’ descriptions. It remains an important reference for anyone assembling, cataloguing, or studying a specialized library of rare and historical books.

corundum, sapphire, Australia.12, gems

V. Stratton surveys the sapphire fields around Rubyvale in the Anakie district of central Queensland, presenting them as an extensive but incompletely developed resource whose prospects depend on stronger markets and improved mining methods. The fields are described as covering approximately 1,200 square miles, about 192 miles west of Rockhampton. Despite important discoveries and growing American interest, mining remains small in scale, intermittent, and largely dependent on individual miners using simple equipment. Sapphires occur in old river gravels from the surface to depths of about 50 feet. Miners sink shafts in promising ground, extract the sapphire-bearing material, and wash it through sieves; an illustrated example uses a spring sieve in a 100-gallon water tank. Stratton reports that no more than about 50 men are mining in the district at any one time, with low financial returns discouraging sustained work and making the field’s potential difficult to assess. The account contrasts occasional valuable finds with the modest circumstances of the mining community. It describes veteran miners, individual claims, accumulated stocks of rough material, and substantial differences between owners’ expectations and buyers’ valuations. Yellow or golden sapphires receive particular praise, while green stones are also described as high quality. Blue sapphires, although prominent in the world market, are generally considered too dark for buyers favoring lighter material, and American purchasers are reported to show greater interest in green stones than in ordinary dark blues. Two recently recovered golden sapphires are each valued at approximately 1,500 Australian pounds, while the Black Star of Queensland, reportedly once used as a doorstop, illustrates the publicity generated by exceptional discoveries. James and Harry Kazanjian’s acquisition of five Rubyvale sapphires is cited as evidence of American attention. Arthur Wirth, president of the New South Wales branch of the Gemmological Association of Australia, anticipates possible American investment in bulldozers and open-cut mining to work the gravels more extensively. His forecast rests partly on uncertainty surrounding supplies from Thailand. Stratton nevertheless records a less active immediate situation: in August 1951, production was virtually at a standstill because many regular miners had left for better-paid work, including timber cutting and kangaroo shooting. The article combines observations of mining practices and local life with an optimistic assessment of future development, while showing that market preferences, labor availability, and miners’ returns constrained exploitation.

gems, jade, jadeite, fei cui, Mesoamerica, Mexico, Guatemala, Costa Rica, Mayans, Olmecs, Aztecs, archaeology, history, archaeogemology, Pre-Columbian jade; Costa Rica; Maya; exchange; iconography, lapidary

Two important studies in Maya archaeology form the foundation of this book: A Study of Maya Art: Its Subject Matter and Development, by Herbert J. Spinden (1913); and The Inscriptions of Peten, by Sylvanus G. Morley (1937–38). The first established, with notable success, a series of stylistic changes in sculpture at a number of the larger Maya sites; the second provided epigraphic decipherments which permitted the dating of many more monuments in the Peten than was formerly possible. With this much more substantial body of dated material than was available at the time of Spinden’s study, we are now able to confirm many of his findings and to elaborate the basis of stylistic appraisal, extending it to all Classic Maya sites. It is because so much reliance has been placed on Morley’s epigraphic work that disagreements between his stylistic appraisals and mine have been stressed in this book. This, however, should not be construed as a derogation of his conclusions, which rest primarily on epigraphic sources. Our differences serve only to indicate the need to establish definite and significant style characteristics on which future discussion can be based. This is the principal aim of this study; it would have been futile to pursue it without the collection of epigraphic data and interpretation which Morley’s work makes available.

synthetic spinel, Verneuil, gems

E.J. Gübelin investigates whether synthetic red spinel was commercially available, correcting a statement in A.K. Seemann’s 1949 account of American synthetic crystals that listed ruby-red and garnet-red spinel among available colors. Literature review and correspondence with W.F. Eppler establish a distinction between the experimental possibility of producing red spinel and the practical manufacture of transparent, durable material suitable for cutting and sale. Gübelin explains that conventional Verneuil production of single-crystal spinel requires a substantial excess of alumina over the equimolar proportions of magnesium oxide and aluminum oxide represented by natural spinel’s formula, MgAl₂O₄. Attempts using the natural proportions instead produce aggregates of differently oriented crystals that crack readily on cooling. Commercial synthetic spinel may contain approximately 3.5 moles of alumina per mole of magnesia. This compositional difference affects the colors produced by added metal oxides: a coloring agent need not impart the same hue to spinel and corundum because their crystal structures differ. Chromium, responsible for red ruby and natural pink spinel, produces dark green in the alumina-rich synthetic spinel under discussion. Gübelin reviews the characteristic absorption and fluorescence associated with chromium and describes contrasting thermal behavior in ruby and green synthetic spinel. Ruby becomes green at approximately 500–600 °C but recovers its original red color on cooling. Green synthetic spinel undergoes precipitation of excess alumina at approximately 950–1050 °C, becoming cloudy; above about 1075 °C, structural changes can produce red coloration accompanied by deterioration of transparency and gem quality. The article interprets these effects through the behavior of chromium-bearing alumina within different crystal structures. M.T. Mackowsky’s published observations and Eppler’s experimental experience agree that red synthetic spinel can be obtained when magnesia and alumina are maintained near a 1:1 molar ratio, but the resulting specimens are generally tiny, cracked, or shattered. Eppler reports that increasing the alumina content toward the proportions needed for satisfactory commercial boules immediately changes the color from red to green. Gübelin therefore concludes that red synthetic spinel is producible in principle, while satisfactory cutting material had not been established as a commercial product at the time of writing. He regards Seemann’s listing as an overlooked error, while allowing that future technical advances might overcome the manufacturing difficulties.

corundum, synthetic corundum.7, Verneuil, Linde, gems

A.K. Seemann reviews the development of American synthetic crystal production during and after the Second World War, explaining the manufacture, properties, and commercial applications of corundum, spinel, star corundum, and titania. Adapted from a presentation to the American Gem Society’s 1949 conclave, the article describes how wartime demand for instrument bearings stimulated a domestic industry that subsequently developed new crystal forms and gemstone materials. The basic Verneuil process is outlined: finely prepared oxide powder passes through an oxyhydrogen flame, melts, and crystallizes on a progressively lowered support. Control of powder supply, flame conditions, and lowering rate determines the growth and dimensions of the boule. Seemann discusses powder preparation by calcining purified salts, the introduction of coloring agents, and the importance of purity, noting that some contaminants become visible even at concentrations of a few parts per million. Chromium produces ruby, while titanium and iron additions produce blue sapphire; various metal oxides provide colors in synthetic spinel. A major American advance was the growth of long, cylindrical sapphire rods, reducing the labor and material loss involved in converting conventional split boules into small bearings. Studies connected crystallographic orientation with splitting, transverse cracking, and deformation at high temperatures. Near the melting point, rods could be bent or stretched, with material oriented at approximately 45° between the c-axis and growth direction proving easiest to deform. Flame polishing offered an economical means of obtaining smooth surfaces and rounded phonograph-needle tips, whose service life also depended strongly on crystal orientation. High-temperature annealing permitted larger whole boules to be worked without splitting. Additional applications included precision sapphire balls for pen tips and decorative use. Seemann identifies synthetic star ruby and sapphire as a particularly striking development, attributing their asterism to fine needles while withholding the manufacturing method pending patent action. The final section treats titania, synthetic rutile, emphasizing its exceptionally high refractive indices and dispersion alongside its relative softness and cutting difficulties. Produced by a modified Verneuil process, the initially black, opaque, oxygen-deficient crystals become transparent after heating in an oxidizing atmosphere, with a corresponding large increase in electrical resistance. The material’s potential applications therefore extend beyond gems to monitoring furnace atmospheres. For gemstone use, crystal orientation, accurate facet angles, and suitable polishing procedures are essential to avoid a cloudy appearance and excessive rounding of facet junctions. Seemann recommends alumina for final polishing and cautions against overheating during sawing, cutting, or polishing because changes in oxidation state can cause discoloration or fracture. The article presents gemstone synthesis and industrial crystal engineering as closely connected fields, with advances in growth control, orientation, annealing, and finishing supporting both jewelry and technical applications.

synthetic corundum.7, ruby, Verneuil, gems

A.E. Alexander investigates the existence and identifying features of “reconstructed” ruby, reporting an experimental rod made from natural ruby fragments and a faceted stone independently judged to have a similar origin. The inquiry arose from repeated encounters with rubies submitted as reconstructed material that proved to be synthetic, leaving Alexander doubtful whether reconstruction was commercially or technically genuine. To test the possibility, he assembled 14 carats of natural ruby chips selected for good color and identifiable natural inclusions, including rutile needles, and submitted them to A.K. Seeman of Linde Air Products Company. Instead of being fused directly into a mass suitable for faceting, the chips were ground to 200 mesh and made into a rod approximately 1½–2 millimeters in diameter and 41 millimeters long. A section was examined longitudinally with a binocular microscope and subsequently prepared as a thin section for petrographic study. Fusion produced a slight loss of color and eliminated recognizable evidence of the original mineral inclusions, even during examination at 450× and 900×. The rod contained spherical and irregular gas cavities, cometlike inclusions with distinct tails arranged in a broadly fan-shaped pattern, and curved growth lines transverse to its length. Its c-axis lay approximately 70° from the rod’s length, while examination between crossed polarizers revealed occasional grains oriented differently from the surrounding mass. During this investigation, a dealer submitted a 1.28-carat faceted ruby that initially resembled an early Verneuil synthetic. Examination by immersion in alpha-monobromonaphthalene instead led Alexander to identify it as reconstructed. Following donation of the stone to the Gem Trade Laboratory, it was examined in July 1948 by B.W. Anderson and E.J. Gübelin at Gübelin’s Lucerne laboratory; both agreed with that interpretation. Features described include peculiar swirl markings, some sharply terminated, four distinct undulating veils, gas cavities, and other inclusions resembling those encountered in natural corundum. Recorded properties were refractive indices of 1.760–1.767, specific gravity of 4.00, bright red fluorescence under ultraviolet radiation and X-rays, and the characteristic ruby absorption spectrum. The article presents these observations as evidence that reconstructed ruby can exist in both rod and faceted forms, while showing that the fusion process can create features resembling synthetic corundum and destroy recognizable inclusions inherited from the natural starting material.

corundum, India.12, Burma.12, Sri Lanka.12, quality.10, gems, Indian lapidary

Sinkankas: A fairly complete general treatment of gemology written in popular terms and presumably meant to replace or supplant the somewhat similar publications above, especially insofar as Iyer emphasizes the gemstones that occur in India, Burma, and Ceylon. The first part treats principles and is followed by a second part on descriptions. Because of the author’s familiarity with native gemstones, this work remains a valuable reference. Commendable features include descriptions of native mining methods used, histories of previous mining attempts in the countries named, and a bibliography that is large, detailed, and paginated! This work is scarce.