 | | Book | | 1982 Jules Roger Sauer ” Foreword For years Brazil has been the major producer of colored stones in...metamorphic rocks, the variety of gem deposits in Brazil is almost infinite. In addition to the mineral...assemblage one might expect from pegmatite dikes, Brazil also produces a very significant output of diamonds...written in English, and beautifully illustrated. “Brazil, Paradise of Gemstones’, by Jules Roger Sauer,...Grande do Norte, in 1953, the precious opals of Pedro I] in Piaui, in 1960, and a turquoise vein near |  | | Journal (issue) | | Minas Gérais, Brazil. See 'The location, geology and mineralogy of gem tourmalines in Brazil' on pp. 263-98...location, geology and mineralogy of gem tourmalines in Brazil Jacques P. Cassedanne, Dr. Sc. *, and Maurice Roditi...Tourmaline, pegmatite, eluvial deposits, gem mining, Brazil © Gemmological Association and Gem Testing Laboratory...the most remarkable coloured gemstones mined in Brazil where, erroneously, for a long time it was marketed...section (Sinkankas cited by Dietrich, 1985). In the Barra da Salina area (Minas Gérais) where the nodules |  | | Journal (issue) | | device|Melee Inspector| Presidium Synthetic Diamond Screener II|SYNTHdetect mounted diamond screening device|CIBJO...Articles 708 Coloured Stone Mining and Trade in Brazil: A Brief History and Current Status By Aurélien...Collection V. L. Villani photo p. 758 Cover Photo: Brazil is the source of a variety of coloured stones,...Gemmological Association of Great Britain ISSN: 1355-4565 ii Cert no. TT-COC-002454 Understanding Gems ™ The...Synthetic Diamond Screener II Released in September 2017, the Synthetic Diamond Screener II from Presidium uses |  | | Book | | BARTORELLI ::• . . .. MINERALS & PRECIOUS STONES OF BRAZIL Sponsored by: VALE MINISTER.IO DA CULTURA ©...Brasileira do Livro, SP, Brazil) Cornejo, Carlos .Minerals & precious stones of Brazil. Carlos Cornejo, Andrea...3. Minerals - Brazil 4. Minerals- Classification 5. Mineralogy 6. Mineralogy - Brazil - History 7. Precious...Precious stones - Brazil I. Bartorelli, Andrea. II. Title. 09-10025 Cover photograph: Crystal of brazilianite...Landmann. CDD-549 Indexes for systematic catalog: 1. Brazil: Minerals and precious stones: Mineralogy and gemology |  | | Book | | original: Norte-Americano: “GEOLOGY AND PHYSICAL OF BRAZIL” GEOGRAPHY Esta tradução & propriedade literarta...publicação da obra “Geology and Physical Geography of Brazil”, pasa satisfazer ao pedido de Louis Agassiz para...1868— (Accowt of o lecture ou the glaciotion of Brazil”) (“Resumo de uma conferência sobre à glaciação...PHYSICAL GEOGRAPHY OF BRAZIL” (Thayer Expedition-Scientific "results of a journey in Brazil by Louis Agassiz...dessa excursão foi publicada na obra “Journey in Brazil”, (*) não sendo, portanto, necessário repeti-lo |  | | Catalog/List | | Tourmaline, Jenipapo District, Itinga, Minas Gerais, Brazil 6.7 cm tall x 6 cm wide 10 12 Wolfenite This...unique. Tourmaline, Barra do Salinas Dist., Coronel Murta, Minas Gerais, Brazil 12 cm tall x 4.6 cm wide...wide 19 20 Opal Precious opals are a hydrated amorphous form of silica (amorphous meaning a non-crystallized...Australia is the locality most associated with precious opal. The precious opals of Ethiopia were only discovered...of flashing rainbow colors that we see here. This opal may be unique. The colors are like no other we have |  | | Journal (issue) | | recently. A good distantvision reading indicated opal, but our customer didn't think it could be, such...nondestructive a n d the material, which was probably opal, was frangible to say the least. A matching density...comparison stone established the stone to be opal. * * * Another opal, which caused me a lot of trouble customerwise...customerwise, not gemmologically, was a black opal purchased as such, mounted in a ring a n d offered for...found the opal colour lipped slightly into the potch and again where potch merged into opal colour. This |  | | Catalog/List | | filling 5mm vugh in lxl inch Basalt Zeolite lxl £5 166 II: ■ GISMONDINE Green road Quarry, Ballyclare, County...S . 326 ■■ OPAL Herl'any, Slanske Mts, east Slovakia Red-brown mass, known as "meat opal" Ix! £3 lx2...Linopolis .Divino das laranjeiras, Minas Gerias Brazil £60 2. GLAUCOPHANE attractive very dark blue matted...specimen Ipe Mine, Governador Valadares Mines Gerais Brazil 1.5 xl.5 inches £65 I! 4. CYR!LOV!TE very rii::h...coverage !avra do Eduardo, Galileia Minas Gerais Brazil £45 5. SKUTTERUDITE excellent coverage of silvery |  | | Journal (issue) | | gia.edu/gems-gemology Multimedia Specialist Pedro Padua Nancy Powers Betsy Winans Editorial Review...geology, and notable localities of diamond mining in Brazil, and outlines plans for future diamond production...in bastnäsite • Flashes and flames in Ethiopian opal • Cat’s eye imitation pen pearls • Negative crystals... Svisero, James E. Shigley, and Robert Weldon Brazil, which commanded global production in the 1700s...Gerais and Mato Grosso, are presented. W hile Brazil is widely known for the production of colored gemstones |  | | Journal (issue) | | Famous Mineral Localities: The Barra de Salinas pegmatites, Minas Gerais, Brazil . . . . . . . . . . . . ....Pakistan, Nepal, California, etc. $15 v.18/#1 Gold-II Issue! Australia, Calif., Breckenridge, Hopes Nose... Famous Mineral Localities: The Barra de Salinas Pegmatites inas Gerais, Brazil Francisco Müller Bastos Rua...Guimaraes 1645 Belo Horizonte, Minas Gerais 30000 Brazil Brazilian tourmaline has been famous among collectors...of all Brazilian localities is the district of Barra de Salinas, encompassing a gem-bearing pegmatite |  | | Report (issue) | | Contents 4 Map: Notable Opal Localities 50 BY BRUCE PAUL GABER 6 The Opal Enigma: Science, History...and Pins Afire: Play of Color in Opal BY MAX WEIBEL Sparkling Opal in Ancient Bones: Precious Relics...vibrant with opal pattern and color. In this extreme close-up of a Lightning Ridge black opal, the field...approximately 3 mm wide. Opal courtesy Jenni Brammall BY ALEX RITCHIE 52 An Opal Glossary of Terms BY...BY SI AND ANN FRAZIER BY PETER HUBER 64 Opal from Mexico: Unsurpassed Fire BY JURGEN SCHUTZ 18 Perfect |  | | Journal (issue) | | it and seeing is believing! WHERE THE BUFFALO, BARRA AND BITS OF GOLD ROAM The final leg of Jack Lange·s...distant relatives. AUSTRALIAN COLO GEM & TREASURE II I have talked to some of the long-term residents...Equipment (Est. 1977) a range of unequalled value! 1·ii=i=l 1• €J=t·3=J-MM=iAutomatic Ground Balance • •...DI HNILaDPAN fllb.11t lllwllllll Dllllll1 lllM fc•II This amazing lightweight pan with its patented spiral...provide clues, as do interference colours as seen in opal. DENSITY. The density of a stone could be roughly |  | | Journal (issue) | | MARKETS Figure 9. Near Nova Era in Minas Gerais, Brazil, the Belmont mine operates using sophisticated...other mines in the area slowed (Weldon, 2006). Brazil witnessed a sustained slump in overall gemstone...in places like the United Arab Emirates, Russia, Brazil, India, and China—locations that would not have...discovered in Paraíba and Rio Grande do Norte states in Brazil in 1989 (Fritsch et al., 1990) and became known...plummeted, mining operations in key centers such as Brazil and Zambia curtailed or ceased production, though |  | | Journal (article/letter/editorial) | | da Pitorra, Laranjeiras, Galiléia Minas Gerais, Brazil T here can be multiple reasons for including...da Pitorra, Laranjeiras, Galiléia, Minas Gerais, Brazil. Intense color is indicative of exposure to higher...the electrical properties, and opposite-handed Brazil twins disrupt the optical properties. Thus, the...crystals, namely Oxford County, Maine; Minas Gerais, Brazil; and Nuristan Province, Afghanistan. The pegmatite...primary rose quartz crystal producers—Minas Gerais, Brazil. Distance to small town Mine Downloaded by [Colorado |  | Maza, Santiago, Collo, Gilda, Morata, Diego, Cuña-Rodriguez, Carolina, Taussi, Marco, Renzulli, Alberto (2021) The Hydrothermal Alteration of the Cordón de Inacaliri Volcanic Complex in the Framework of the Hidden Geothermal Systems within the Pabelloncito Graben (Northern Chile) Minerals, 11 (11) 1279 doi:10.3390/min11111279 | Journal (article/letter/editorial) | | acid-sulfate alteration with alunite + kaolinite + opal CT + anatase, indicating the presence of a steam-heated...steam-heated blanket with massive fine-grained silica (opal-CT), likely accumulated in mud pots where the intersection...the paleowater table with the surface occurred; (ii) argillic alteration with kaolinite + hematite +...alkaline-chlorine water bodies and laterally associated with (ii) calcite + aragonite deriving from bicarbonate waters...diatom remnants, in addition to alunite + kaolinite + opal CT + anatase assemblages, is consistent with a superimposition |  | | Journal (issue) | | found in the seas off the south-eastern USA to Brazil and N. subnodosus in the seas off western Central...Minas Gerais, Brazil 2. Department of Mining and Geology, Federal University of Paraíba, Brazil Abstract:...Laboratory of Great Britain (Shigley et ah, 2000) and Brazil (Ferreira, 1997) have sparked renewed interest...the only garnet variety that does not occur in Brazil (Delaney 1996). Colour-change garnets found in...Teöfilo Poaî â )e Otoni 8W ^ ö y ^ f ^ t ) 16°S Barra doCuieté -0~ Beio Horizonte ü Romaria Mine Minas |  | | Journal (article/letter/editorial) | | specimen is from the Pederneira mine, Minas Gerais, Brazil. John S. White specimen and photo. M any years...looked very much like the green elbaite shell from Brazil in figure 1. She proposed that due to subtle differences...observed on the interior of the green shell from Brazil (fig. 1). Subsequent to this, she writes, the brown...with albite, Urubu mine, Itinga, Minas Gerais, Brazil. This is the specimen that was sacrificed to produce...and is from the Urubu mine, Itinga, Minas Gerais, Brazil. Figure 3b (right). End view of the same specimen |  | | Journal (issue) | | FEATURE ARTICLES Gem Pegmatites of Minas Gerais, Brazil: The Tourmalines of the Araquai Districts Keit-h...tourlnaline thon anywhere else in the world-Minos Gerais, Brazil; the other with (I new locality for red tourmaline-Zcrmbia...his extensive travels in the mining regions of Brazil. Mr. Proctor received an M.S. in molecular biology...graduate gemologist. GEM PEGMATITES OF MINAS GERAIS, BRAZIL: THE TOURMALINES OF THE ARACUAI DISTRICTS By Keith...tourmaline was not discovered until the mid-1500s, in Brazil. Even then, it was mistakenly heralded as emerald |  | | Journal (article/letter/editorial) | | Magnesian Clays Manuel Pozo 1, * 1 2 * and José Pedro Calvo 2 Department of Geology and Geochemistry...(mudflat) Neoformation Feldspars. Cal. Calcite. Opl. Opal. Brt. Baryte. Zeo. Zeolites. Gp. Gypsum. Clt. Cristobalite...content (<10 wt.%) and traces of sepiolite, smectite, opal, mica and dolomite. The palygorskite in the Guanshan...detrital input (ii) runoff, lake water and groundwater hydrochemistry (Figure 7). and (ii) runoff, lake...Mg-clays and related carbonates in the Pre-salt Barra Velha Formation (offshore deals with the study of |  | | Journal (issue) | | deposits of alexandrite, cat's-eye and chrysoberyl in Brazil' pp. 333-54) ISSN: 0022-1252 F.G.A. your key...back as 1761, but in modern times (post World War II) it has not been the accepted practice, ie., in the...deposits of alexandrite, cat's-eye and chrysoberyl in Brazil JacquesCassedanne, Cassedanne, D.Sc.,* Maurice...Fundiio, Fundão, 21,910, Rio de Janeiro, Janeiro, Brazil *Institute of Geosciences UFRJ-CNPq, Cidade Universitaria...Ipanema, 22,410, 22,410, Rio de Janeiro, Janeiro, Brazil **Maurice Roditi Jewellers, distinguished: Abstract |  | | Report (chapter) | | sub-millennial-scale variability in sediment colour from the Barra Fan, NW Scotland: implications for British ice sheet...investigation of glacier-influenced sedimentation on the Barra Fan, NW Scotland. Lightness (L*) and reflectance...significant increase in sediment delivery to the Barra Fan. Prior to 30 ka BP, strong Dansgaard/Oeschger...predating the main Laurentide IRD signature. On the Barra Fan, NW Scotland, Knutz et al. (2001) documented...limits of the Barra Fan, NW Scotland as part of the IMAGES programme (Fig. 1). The Barra Fan extends from |  | | Journal (issue) | | Namibia, as well as Madagascar), South America (Brazil and Colombia), central and southern Asia (Sri Lanka...Pakistan; and pink to red tourmalines from Nigeria and Brazil. Diamond was mined in northern Canada for the first...diamond, garnet, jade [both jadeite and nephrite], opal, peridot, quartz, spinel, tanzanite, topaz, and...mining also continued at traditional sources in Brazil and Africa. Large quantities of Brazilian emeralds...reserves and reduced demand. Emerald production in Brazil has since continued to decline. Several sources |  | | Book | | ltatiaia, Conseilheiro Pena, Governador Valadares, Brazil (Roger Titeux collection, France) 4 inches. Above:...inches. Right: Rutile in quartz, lbitiara, Bahia, Brazil (Yves Gillet collection, France) 1.2 inches. Preceding...Preceding pages: A Tourmaline, Minas Gerais, Brazil (4.2 inches) B Tourmaline, Queen Mine, San Diego County...gems or displaying a splendid irridescence, like opal or labradorite, for example, or the massive stones...Afghanistan, turquoise from Persia, jade from China, opal from Hungary, quartz from the Alps, agates and carnelians |  | | Journal (issue) | | December 1932, offering specimens from Washington and opal from Nevada, from his home address in Spokane. In...article with Henry Dake in Rocks & Minerals entitled “Opal from the Columbia Plateau.” He was President of... from the São Geraldo do Baixio, Minas Gerais, Brazil. Calcite, 11.3 cm, from Wenshan Prefecture, Yunnan...Tantalite-(Fe), 7 cm, from Galileia, Minas Gerais, Brazil. Jeff Scovil photo. Supplement to the Mineralogical...from the Xanda mine, Virgem da Lapa, Minas Gerais, Brazil. Jeff Scovil photo. Pyromorphite, 10 cm, from |  | | Book | | .................. Mexican Opal ........................... Mexican Opal Names............... San Juan...have been exploited in commercial quantities are opal and agate. 4 The literature on the gemology and...not exploited commercially until after World War II. The first Mexican agate to be collected for export...from near Alamos, Sonora. Agate, jasper, and common opal, much of it very attractively patterned and colored...Gold-massive niccolite containing Some of Mexico’s finest opal is mined minor amounts of annabergite, gersdorf- |
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