 | | Book | | GEMSTONES of East Africa Burundi, Kenya, Rwanda, Tanzania and Uganda Bruce Cairncross Published by Struik...resources 12 Burundi 13 Kenya 14 Rwanda 16 Tanzania 17 Uganda 20 Gemological properties 21 A to...through Tanzania, Kenya, Ethiopia and into the Sudan - has blessed East Africa, Kenya and Tanzania, with...starting in what was then Tanganyika ( now mainland Tanzania) and then progressing to Kenya - I am proud to...countries are among the finest in the world. The region and its gems are particularly dear to my family |  | | Catalog/List | | Signature® Internet Session 2 Heritage Auctions Design District Annex 1518 Slocum Street • Dallas, TX 75207 (HERITAGELive...the Tsumeb Mine (as well as other mines of the region) were still in production in the 1970s. You will...Azurite Level 8, Tsumeb Mine, Tsumeb, Otjikoto Region, Namibia If the attachment point on the back of...Klein Spitzkopje, Spitzkopje Area, Karibib District, Erongo Region, Namibia Klein Spitzkopje in Afrikaans...Pseudomorph after Azurite Tsumeb Mine, Tsumeb, Otjikoto Region, Namibia Some of the best things to come from the |  | | Journal (issue) | | (7) 2.14 ct blue sapphire, (8) 23.18 ct blue spinel, (9) 4.82 ct purple sapphire, (10) 5.32 ct Paraíba...1.15 ct purplepink sapphire, (16) 5.54 ct spessartine, (17) 8.04 ct orange sapphire, and (18) 3.48 ct...Asia (Myanmar, Thailand, and Vietnam), Africa (Tanzania, Kenya, Zimbabwe, Nigeria, and Namibia, as well...a wide variety of colored stones from southern Tanzania; spessartine garnet from Nigeria and Namibia;...northern Canada for the first time. Names such as Tunduru, Ilakaka, and Ekati were unknown to the gem trade |  | Giuliani, Gaston, Fallick, Anthony, Rakotondrazafy, Michel, Ohnenstetter, Daniel, Andriamamonjy, Alfred, Ralantoarison, Théogène, Rakotosamizanany, Saholy, Razanatseheno, Marie, Offant, Yohann, Garnier, Virginie, Dunaigre, Christian, Schwarz, Dietmar, Mercier, Alain, Ratrimo, Voahangy, Ralison, Bruno (2007) Oxygen isotope systematics of gem corundum deposits in Madagascar: relevance for their geological origin. Mineralium Deposita, 42 (3) 251-270 doi:10.1007/s00126-006-0105-3 | Journal (article/letter/editorial) | | The oxygen isotopic ratios (18O/16O) of ruby and sapphire from primary deposits are a good indicator of...wide spread between −0.3 and 16.5‰. The ruby and sapphire found in placers linked to alkali basalt environments...placer deposits from Sri Lanka, Madagascar, and Tanzania have a large variety of colored sapphires and...blue sapphire, syenite for yellow, green, and blue sapphire, and skarn in marbles for blue sapphire. Keywords... Oxygen isotopes . Corundum deposits . Ruby . Sapphire Miner Deposita (2007) 42:251–270 gem quality |  | | Journal (issue) | | emerald mine is part of Colombia’s Muzo mining region, an 800 km2 area that encompasses the famous Muzo...emerald district in Colombia, and it is the most productive and well-known emerald mining region in the...historic mine to other famous producers in the region. Keywords: Colombia, emerald, geology, inclusions...Peñas Blancas, located in the famous Muzo mining district. This mine has rarely been mentioned in gemmological...is somewhat different from the three other Muzo-region mines, the fine quality of the emeralds (e.g., |  | | Journal (issue) | | South Korea Kamal Kothari, India Bhadresh Pandit, Tanzania Clement Sabbagh, Brazil Capt. Ramji Sharma, Japan...of the to the UAE, during the Dubai show where region. To aid ICA exhibitors, worldwide financial crisis...computer equipment at the schools in the Tourmalina district of Minas Gerais. The ICA contribution is part...and brighter compared with those from the Tsavo region. While a problem in small stones where it results...potential. Tsavorite is commercially mined in Tanzania, Kenya and Madagascar, mainly from deposits located |  | | Journal (article/letter/editorial) | | trace elements in gem-quality corundum (ruby and sapphire). Nonetheless, the corundum structure is relatively...metamorphic-type sapphires from Sri Lanka, Madagascar, and Tanzania were studied here using LA-ICP-MS, electronprobe...cooling and annealing at a temperature lower than sapphire formation. The studied sapphires suggest the likely...on their geographic origin. Keywords: Corundum, sapphire, exsolution, immiscibility, gemology, trace element...inclusions in gem-quality corundum, Al2O3 (ruby and sapphire). Frequently encountered oriented oxide inclusions |  | | Journal (issue) | | .......................................... 47 Tanzania.................................................Takada, Japan Dong Keuk Kim, Korea Bhadresh Pandit, Tanzania Janet Ann Russell, Thailand Surasit Sriorathaikul...Ambassador, Pakistan; Eric Saul, ICA Ambassador, Tanzania; Thomas R. Yager; Dr. Dietmar Schwarz, Switzerland;...minister of mineral resources who said he believed the region needed new areas to prospect, as there have been...recognized for its bright colors and good stability. Sapphire N ew South Wales: Production is at its lowest |  | | Journal (issue) | | alluvial sapphires from Russia’s Jewish Autonomous District. 266 A New Deposit of Gem-Quality Grandidierite...pearls • Black star sapphire filled with lead glass • Green lead glass–filled sapphire rough • Large crystal...in Mexico • Colored gemstone mining update from Tanzania • Purple pyrope-almandine garnet from Mozambique...rhodochrosite • Rubies reportedly from Pokot, Kenya • Blue sapphire reportedly from Badakhshan, Afghanistan • “Punsiri”-type...“Punsiri”-type spectral features in natural yellow sapphire • Large aqueous primary fluid inclusion in amethyst |  | | Journal (issue) | | Argyle, courtesy of Rio Tinto; (4) an 11.16 ct sapphire from Madagascar, GIA Collection no. 31618; (5)...of Aurora Gems; (6) a 9.15 ct ruby from Winza, Tanzania, courtesy of Hakimi & Sons; (7) a 14.80 ct “golden”...fields. Likewise, beryllium diffusion of ruby and sapphire brought together geologists, gemologists, and...exports from Myanmar disrupted supply channels for sapphire and ruby. And the proliferation of new sales avenues...were combined under the jurisdiction of the U.S. District Court of New Jersey 168 PRODUCTION AND MARKETS |  | | Journal (issue) | | heat treatment on corundum. A non-heat-treated sapphire will still not be valuable if, for instance, it...too pale or too dark. However, a heat-treated sapphire with good color and clarity will not have the...the same value as a similar-quality untreated sapphire. Of course, there are several critical differences...differences between the treatments in emerald and sapphire. With heat treatment of sapphires, the stone itself...kilobars and temperatures of 1400°C –1700°C. In this region of the diamond stability field (see figure 2), |  | | Journal (article/letter/editorial) | | is called pink sapphire, yellow sapphire etc., while the blue gem corundum is sapphire. Red, pink and...precursor (Polat et al. 2009). The greater Fiskenæsset region was meta; 50°W Grædefjord ; den æsfjor ;...Maniitsoq Storø Kapisillit Nattivit Winza Umba Tunduru Sahabano Zazafotsy 60 Qaqqatsiaq Aappaluttoq...Chanthaburi in Thailand, Pailin in Cambodia and Winza in Tanzania. Rubies from all these localities are hosted by...granulite-facies relations in the Fiskenæsesset region, southern West Greenland. The Journal of Geology |  | | Journal (issue) | | Richelieu Sapphires, a pair of rare and magnificent sapphire and diamond ear pendants containing two Kashmir...Rochefoucauld, in 1905. An exceptional unmounted Burmese sapphire of 114.73 ct (SSEF report 69915) was another highlight...2013 a rare Kashmir sapphire of 19.88 ct for 3’371’750 Swiss Francs. This sapphire was set with two diamonds...gemstone diversity going far beyond just ruby and sapphire. rr On the road from Dattaw to Mogok, the entrance...week, we were able to visit many famous ruby and sapphire mines in the Mogok Stone Tract, such as Baw-mar |  | | Journal (issue) | | since over 25 years abroad, mainly in Thailand, Tanzania, Kenya and Madagascar. He speaks besides German...the trip from Nairobi and visited Madagascar and Tanzania within three weeks. It was surprising to see how...Chanthaburi as in Tananarivo or in Mombasa or Arusha. Tanzania Werner Spaltenstein sat in the office of his agent...(vanadian green grossular garnet), tanzanite, sapphire in fancy colours, pink and mauve spinels and green...plane Fig.2 River landscape at the Muhuwesi near Tunduru (STanzania) containing gem minerals in its gravels |  | | Journal (issue) | | to those found in the Umba valley and Tunduru area in Tanzania whereas the blue sapphires are reminiscent...similar to the alluvial deposits of Sri Lanka and Tanzania and the three areas may have been part of single...internal characteristics, Madagascar, padparadscha, sapphire Introduction M adagascar has been well known...the east coast (Schwarz and Henn, 1992) and the sapphire fields of Andranondambo in the southeast of the...of the discovery spread, people from the whole region rushed to the area seeking their fortune in gemstones |  | Giuliani, Gaston, Groat, Lee, Fallick, Anthony, Pignatelli, Isabella, Pardieu, Vincent (2020) Ruby Deposits: A Review and Geological Classification. Minerals, 10 (7) 597 doi:10.3390/min10070597 | Journal (article/letter/editorial) | | uncommon on Earth but the gem varieties of ruby and sapphire are relatively rare. Gem corundum deposits are...Vatomandry; (2) Andriba; (Antsirabe-Antanifotsy region, Soamiakatra-Ambohimandroso; Ambohibary); (3) Zazafotsy;...Zazafotsy; Ankaratra (Antsirabe-Antanifotsy region, Soamiakatra-Ambohimandroso; Ambohibary); (3)IlakakaZazafotsy;...John Saul mine; Penny Lane; Aqua, Hard Rock). Tanzania: (10) Umba (9) Mangare (Rockland-formerly John...John Saul mine; Penny Lane; Aqua, Hard Rock). Tanzania: (10) Umba valley; (11) Longido, Lossogonoi; (12) |  | | Journal (issue) | | vivid “canary” yellow elbaite from the Lundazi District of eastern Zambia, the most important source of...emerald carving • Gold coated onyx • Double-star sapphire • Imitation turquoise 366 Gem News International...Namibia • Andradite from Pakistan • Axinite from Tanzania • Baddeleyite from Mogok, Myanmar • Chrysocolla...and chondrodite from Tanzania • Transparent dumortierite and sapphirine from Tanzania • Brazilian blue “opal”...am, out in the middle of the Tanzanian bush at Tunduru, spitting distance from Mozambique, on the Muhuwesi |  | | Journal (article/letter/editorial) | | Joel E. Arem Luytonsville, Maryland Ruby and Sapphire by Richard W. Hughes. RWH Publishing, 4946 Clubhouse...something representative of the actual ruby and sapphire marketplace. Moreover, these advertising pages...book is opened flat. It is arguable that ruby and sapphire are the most important gemstones in the world...BeharaBekily area of Madagascar and the Tunduru area of Tanzania. This book isfun to read, simple enough |  | | Journal (issue) | | 536 Geographic Origin Determination of Blue Sapphire Aaron C. Palke, Sudarat Saeseaw, Nathan D. Renfro...Shane F. McClure In some cases, the value of a sapphire depends strongly on its geographic origin. This...details the origin data GIA has collected for blue sapphire and describes its methodology for using the data...left: a 64.45 mm Sri Lankan sapphire crystal, a 24.34 ct Sri Lankan blue sapphire, two cuprian tourmalines...and 45.74 ct), a 16.65 mm pink-purple Sri Lankan sapphire crystal, a 10.90 ct Burmese ruby, and an 11.11 |  | D’Ippolito, Veronica, Andreozzi, Giovanni Battista, Hålenius, Ulf, Skogby, Henrik, Hametner, Kathrin, Günther, Detlef (2015) Color mechanisms in spinel: cobalt and iron interplay for the blue color. Physics and Chemistry of Minerals, 42 (6) 431-439 doi:10.1007/s00269-015-0734-0 | Journal (article/letter/editorial) | | Origin Light blue Tunduru, Tanzania Nat.4 30070 1 mm Greenish blue Tunduru, Tanzania 0.2 mm Dark blue...made it possible to use them as highly priced sapphire analog in gemology. Blue pigment based on hercynite...different geological environments around the world (Tanzania, Spain, Italy and USA) were studied. Four samples...photomultiplier as detector. Spectra in the NIR spectral region from 1,100 to 2,000 nm (9,091–5,000 cm−1) were...a large set of absorption bands in the spectral region between 10,000 and 20,000 cm−1. In accordance with |  | | Journal (issue) | | 45 NO. 4 Ruby-Sapphire Review Nanocut Plasma-Etched Diamonds Chrysoprase from Tanzania Demantoid from...__________________ 236 Carat Points 260 pg. 251 Ruby and Sapphire Production and Distribution: A Quarter Century...Chrysoprase and Prase Opal from Haneti, Central Tanzania James E. Shigley, Brendan M. Laurs, and Nathan...the Kagem mine, Zambia • Yellow grossular from Tanzania • An unusual blister pearl • Myanmar report •...worldwide. This sapphire necklace, designed by David Webb, has approximately 700 carats of sapphire beads. The |  | | Journal (issue) | | Spinels from Sri Lanka 54 The Spinels of Mahenge, Tanzania In Search of Cobalt Blue Spinel in Vietnam Spinel...InColor Summer 2019 A 7.13-ct spinel from Mahenge, Tanzania. Cover image: Prangpak Ruahong, Nomads. 40 100...include the colored gemstones ruby, emerald, and sapphire. This paved the way for Greenland Ruby to join...Greenland Ruby’s mine produces both ruby and pink sapphire. “We’re delighted to begin the process of becoming... InColor Fura Announces Acquisition of Australian Sapphire Mining Project Vietnam's Gemstone, Precious Metal |  | | Journal (issue) | | Index ABOUT THE COVER: The historic Ouro Preto region of Minas Gerais, Brazil, is world-renown for the...Capiio mine is one of the most productive in the region. This mine and the superb topazes produced there...Today, the region lznown i n the world gem market as the Ouro Preto Imperial topaz district comprises...operation is the Cap50 mine, in the Rodrigo Silva district. Specimens and information about that mine were... Figure 1. The fine Imperial topazes from the region near Ouro Preto, in Minas Gerais, Brazil, are most |  | | Journal (issue) | | years, Vietnam has become a significant ruby and sapphire-producing country in south-east Asia {Figure 1)...thousands of local peasants searched for ruby and sapphire and in 1991, alluvial sapphires related to basalts...during field mapping in the An Phu area (Luc Yen district), 270 km north of Hanoi (Figure 3). This corundum...Nuoc Ngap, Hin Om, Khau 174 The Quy Chau mining district is located about 120 km north-west of the city...Between 1989 and 1990, 10,000 miners migrated to the region from all over Vietnam. The illegal mining activities |  | | Journal (issue) | | 322 Rubies and Sapphires from Winza, Central Tanzania Dietmar Schwarz, Vincent Pardieu, John M. Saul...“D-TO-Z” DIAMONDS diamonds from the Cape of Good Hope region, and “Jager” for colorless diamonds with strong...of color in a diamond. In the New York jewelry district on Maiden Lane, neighboring buildings were painted...the blue region of the spectrum, as it is the absorption area of wavelengths in this region that allows...the 6-watt lamps used in the past. Here, the UV region shows good agreement between the three lamps. Note |
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