 | | Journal (article/letter/editorial) | | Variably colored grossular specimens from the Jeffrey mine in Canada have previously been featured as a Connoisseurâs...Tanzanian tsavorite has types 2, 3, and 4 represented; Kenya tsavorite is only types 2 and 4. The original discovery...tsavorite was named after Tsavo National Park in Kenya, located close to the border with Tanzania (figs...tsavorite in Tanzania and subsequent discovery in Kenya in 1970 by the geologist and gem prospector Campbell...Bridges and Walker (2014). Prior to its discovery in Kenya, Bridges had found âtsavoriteâ Figure 2. A rough |  | | Book | | noted gemologist and geologist, Dr. Peter Keller. Kenya and Tanzania are revealed in their full mineralogical...200 known here-holds the productive Mwadui diamond mine, known for Yeryfine, rare, pink diamonds. Emerald...of the 'Irelawney Collection of the Los Angeles County Museum of Natural History. ⊠Figures vii Foreword...Tanzania 32 Sapphire from Kenya 42 Ruby from Mangari, Tsavo West National Park, Kenya 44 Chapter 4. Emerald...Red Dravite Tourmaline from the Narok District, Kenya 99 Uvite-Dravite Chrome Tourmaline 99 Chapter 8 |  | Jacob, J.-B., Martelat, J.-E., Goncalves, P., Giuliani, G., Devidal, J.-L., Feneyrol, J., Omito, E., Ichang'I, D. (2018) New P-T-X conditions for the formation of gem tsavorite garnet in the Voi area (southwestern Kenya) Lithos, 320. 250-264 doi:10.1016/j.lithos.2018.09.010 | Journal (article/letter/editorial) | | formation of gem tsavorite garnet in the Voi area (southwestern Kenya) J.-B. Jacob, J.-E. Martelat, P. Goncalves...formation of gem tsavorite garnet in the Voi area (southwestern Kenya). Lithos (2018), doi:10.1016/ j.lithos...formation of gem tsavorite garnet in the Voi area (southwestern Kenya) J-B. Jacoba,*, J-E. Martelata,**, P...Mines and Geology Department Taita-Taveta, P.O. Box 1043-80304, Wundanyi, Kenya h M Department of Geology...Riverside drive, P.O. Box 30197-00100 GPO, Nairobi, Kenya ïȘïȘ Principal corresponding author ED *Corresponding |  | | Book | | MINERALS& GEMSTONES of East Africa Burundi, Kenya, Rwanda, Tanzania and Uganda Bruce Cairncross Published...chromian diopside crystals on large, well-formed grey graphite crystals, field of view 3 cm - Philip Hitge specimen...Africa 10 East African resources 12 Burundi 13 Kenya 14 Rwanda 16 Tanzania 17 Uganda 20 Gemological properties...through Tanzania, Kenya, Ethiopia and into the Sudan - has blessed East Africa, Kenya and Tanzania, with...now mainland Tanzania) and then progressing to Kenya - I am proud to say that the coloured gemstones |  | | Journal (issue) | | on the growth of vanadium grossular garnets in Kenya R.M. Key, FGA*, andP.G.Hill** *British Geological...growth of green vanadium grossular garnet in SE Kenya ascertainedthe chemistry of the host graphitic gneisses...gneisses and on metamorphic conditions in SE Kenya are preby Pohl and Neidermayr (1978) are confirmed...complex Upper Proterozoic to around garnet pods in SE Kenya are not retrogressive Lower Phanerozoic province...their work in SE Kenya, Pohl and Neider- also found on either side of the Tanzania/Kenya mayr (1978) concluded |  | | Report (issue) | | pocket in the McEarl Ridge mine near Jessieville, also called the James Zigras mine, because that worthy collector...Quartz, 14.7 cm, from the Zigras (McEarl Ridge) mine, Jessieville, Arkansas. The Arkenstone specimen...specimens are attributed to a mine named, aptly enough, the Green Fluorite mine, Manaoshan Mountain, Suxian...matrix. Fluorite, 11.6 cm, from the Green Fluorite mine, Manaoshan Mountain, Suxian district, Chenzhou Prefecture...a summer 2017 find at Quan Zhou city, Yong Chun County, Fujian Province. Gemmy, lushly blue-purple cubic |  | | Journal (issue) | | (lithium tourmaline) was made at the Dunton gem mine, Newry, Maine, U.S.A. The narrative of discovery...England "watermelon" tourmaline had come from this mine in years gone by, although most of it was not facet-grade...after two years of semi-continuous operation of the mine. T h e elbaite is being mined from collapsed gem...comparison was m a d e using the Spex Industries graphite standards a n d Spex mix. 363 TABLE II SPEGTROGRAPHIG...Instrumentale, 6, 127. 385 RED DRAVITE FROM KENYA By PETE J. DUNN, M.A., F.G.A., JOEL E. AREM, Ph |  | Arneth, J.D., Schidlowski, M., Sarbas, B., Goerg, U., Amstutz, G.C. (1985) Graphite content and isotopic fractionation between calcite-graphite pairs in metasediments from the Mgama Hills, Southern Kenya. Geochimica et Cosmochimica Acta, 49 (7) 1553-1560 doi:10.1016/0016-7037(85)90260-1 | Journal (article/letter/editorial) | | Graphite content and isotopic fractionation between calcite-graphite pairs in m~~sed~rn~nts frarn the...the Mgama Hills, Southern Kenya J. D. ARNETW, M. SCHIDLQWSKI Mu-P~anck-~nstitot firChemie (~t~Hahn-Institut)...from the Mgama Hills region, Kenya, contain conspicuous quantities of graphite, most probably derived from...from organic progenitor materials. The highest graphite contents (5.1~20.4%3are found in schists whereas...material, with the highest isotopic ratios in graphite from the marbles (SâC - -7.3 rt 5.0%: ft = IO) |  | | Journal (article/letter/editorial) | | characteristics of inclusions (calcite, anatase, graphite etc.) between natural and heat-treated tanzanite...weakened in the heat-treated T7 sample. The black graphite inclusions are often scattered or have a dotted...Raman peak of graphite, thus representing the order and structural incompleteness of graphite. In addition...process is controlled by the boudinage in the graphite gneiss [8]. According to their fission track dating...g., other colored zoisite (brown and yellow), graphite, diopside, pyrite, quartz, grossular (tsavorite) |  | Dachs, E., Geiger, C. A., Benisek, A., Grevel, K.-D. (2012) Grossular: A crystal-chemical, calorimetric, and thermodynamic study. American Mineralogist, 97 (8) 1299-1313 doi:10.2138/am.2012.4047 | Journal (article/letter/editorial) | | two different garnets from the wellâknown Jeffrey mine locality of Asbestos, Quebec, Canada (Allen and...green in color and comes from a locality at Lualenyi, Kenya (Gr-L/K), that is well known for its tsavorite...composition (see below) it may also originate from Lualenyi. All the natural garnets occur in singleâcrystal...measured with a Siemens Dâ500 diffractometer having a graphite secondary monochromator in stepâscan mode with...conditions/locality Chicago; T = 1250 °C, P = 25 kbar, 3 h in graphite container Bayreuth; T = 1250 °C, P = 25 kbar, |  | Feneyrol, J., Ohnenstetter, D., Giuliani, G., Fallick, A. E., Rollion-Bard, C., Robert, J.-L., Malisa, E. P. (2012) EVIDENCE OF EVAPORITES IN THE GENESIS OF THE VANADIAN GROSSULAR 'TSAVORITE' DEPOSIT IN NAMALULU, TANZANIA. The Canadian Mineralogist, 50 (3) 745-769 doi:10.3749/canmin.50.3.745 | Journal (article/letter/editorial) | | V2O3), V-bearing rutile (up to 1.9 wt.% V2O3), and graphite. This rock is affected by calcic metasomatism...(lens I) and a calcite-scapolite-diopside-sulfides-graphite lens (lens II). This last unit is characterized...Mozambique Belt (Walton & Marshall 2007) of southeastern Kenya (Pohl & Niedermayr 1978, Suwa et al. 1996), northeastern...2010a). The presence of scapolite in southeastern Kenya (Suwa et al. 1996) and gypsum and anhydrite in northeastern...sillimanite-biotite gneiss, kyanite or sillimanite-graphite gneiss, biotite-graphite gneiss, calc-silicate rocks, quar |  | Giuliani, Gaston, Dubessy, Jean, Ohnenstetter, Daniel, Banks, David, Branquet, Yannick, Feneyrol, Julien, Fallick, Anthony E., Martelat, Jean-Emmanuel (2018) The role of evaporites in the formation of gems during metamorphism of carbonate platforms: a review. Mineralium Deposita, 53 (1) 1-20 doi:10.1007/s00126-017-0738-4 | Journal (article/letter/editorial) | | vanadium-rich zoisite, called tanzanite, from Tanzania, Kenya and Madagascar, and lapis-lazuli in marble and/or...flakes of phlogopite in a marble matrix, Minh Tien mine, Luc Yen mining district, Vietnam, 2 Ă 1 cm. e Nodule...tsavorite from the Tsavolite mine, Mangare mining district, Voi region, Kenya, diametre of the nodule (on...or lenses; p: calc-silicate rocks; q: kyanite-graphite gneiss; r: dolomitic marble with anhydrite levels...residues of dust not cleaned by the water jet in the mine. Photos b to d: Y. Branquet and Photo e: G. Giuliani |  | | Journal (issue) | | Pakistan and Vietnam|Bicoloured grossular from Kenya|Jade-like materials sold in Myanmar|Blue kyanite...Tanzania|Rainbow moonstone from Malawi|News from the Oceanview mine, Pala, California|Scheelite from Inner Mongolia|Aging...Discoverer of TsavoriteâCampbell Bridgesâand His Scorpion Mine By Bruce Bridges and Jim Walker Gemmological Briefs...Kambanga, Kenya Light yellow-green grossular from Kambanga, Taita-Taveta District, Voi, Kenya, is notable...grossulars (0.61 and 0.42 ct) are from Kambanga, Kenya. Photo by Dirk van der Marel. The darker parts |  | Feneyrol, Julien, Giuliani, Gaston, Ohnenstetter, Daniel, Rondeau, Benjamin, Fritsch, Emmanuel, Fallick, Anthony E., Ichang'i, Daniel, Omito, Edward, Rakotondrazafy, Michel, Ranatsenho, Madison, Lallier, Florent (2014) New typology and origin of tsavorite based on trace-element chemistry. European Journal of Mineralogy, 26 (2) 293-308 doi:10.1127/0935-1221/2014/0026-2367 | Journal (article/letter/editorial) | | University of Nairobi Nairobi, Kenya 7 Mines and Geology Department, Wundanyi, Kenya 8 FaculteÌ des Sciences...geographic provenance of economic tsavorite from Kenya, Tanzania and Madagascar. Key-words: tsavorite,...(Bridges, 1974). The economic deposits are located in Kenya, Tanzania and Madagascar but other small occurrences...Tsavorite is mined presently only in southeastern Kenya (Pohl & Niedermayr, 1978; Suwa et al., 1996; Feneyrol... Fig. 1. Crystal of tsavorite associated with graphite and calcite from Merelani (Tanzania). Crystal |  | | Journal (issue) | | bicolored tounnaline (12.90 ct), all from the Himalaya mine (California). Thestones were faceted by PalaInteri~ntional...the Virgem da Lapa group, thc Salinas mine, and the Ouro Fino mine are especially noteworthy and are described...lzunzites) were also found in this district, in the Neves mine (Lindner, 1966, 1967; Lindner and Rolff, 1968; Rolff...green and blue-green tourmaline from the Pirineus mine is among the best ever found in Brazil, but only...(Levon Nercessian, pers. comm., 1985). The Piaui mine also produced fine green and blue-green rough, approximately |  | | Journal (issue) | | and fluid). Other inclusions such as feldspar, graphite and mica have been reported only in a few stones...structures and colour zoning, spinel lamellae, graphite, feldspar, mica Rare 5.79 0.70 4.91 0.01...radiation at 1.5405 Ă
, (delta lambda 0.0038 Ă
) and a graphite monochromator. Measurements were taken between...tourmalines (dravites and uvites) from East Africa (Kenya and Tanzania) have been known in the gem trade since...and gas) Rarely-observed inclusions Rutile, graphite, xenotime Refined powder data determined for |  | | Journal (issue) | | locally and in the trade as the original tanzanite mine is actually a mining belt about 4 x 1 lzm which...mineralogy at the Natural History Museum of Los Angeles County, Los Angeles, California; and Dr. Krupp is a physicist...West Germany, and has made more than 60 trips to Kenya and Tanzania to purchase gem rough. Acknowledgments:...Campbell R. Bridges, of Bridges Exploration (Nairobi, Kenya), for helpful comments on the manuscript and for...mining has been based in an area to the south of the Taita Hills Notes and New Techniques tsavorite crystals |  | | Journal (issue) | | quality (tsavorite) is known from East Africa (Kenya, Tanzania; Bridges, 1974) and, to a lesser extent...including plagioclase (anorthite), diopside, quartz, graphite and sphene, minerals which may be partially or...garnet Location 1 Madagascar (Gogogogo) Kenya (Lualeni)1 Kenya (Lualeni) Rl SG 1.742 3.62 1.743 3.61...occurred in the gemmological literature spelled Lualenyi J. Gemm., 1997, 25, 6, 391-393 Some physical...characteristics similar to those measured for specimens from Kenya, Tanzania (GĂŒbelin and Weibel, 1975; Manson and |  | | Journal (issue) | | The Horse Gully Mine is comprised of two open-cut pits on opposite sides of the mine office and wash...undoubtedly the highest capacity of any sapphire mine in Australia, if not the world. After the large...under but a couple of feet of topsoil. The open-cut mine is more than a thousand feet long and half as wide...Excavation of the sapphire-bearing gravels at the Stellar mine on the Horse Gully. FIG. 4. A wash plant operated...from Nullamanna and 6 miles downstream from Stellar mine on Horse Gully. The half mile wide flood plain of |  | | Journal (issue) | | marketed, and merchandized. In diamonds especially, the mine-to-market process has been severely tested. Vertical...(Myanmar, Thailand, and Vietnam), Africa (Tanzania, Kenya, Zimbabwe, Nigeria, and Namibia, as well as Madagascar)...reference to the country rather than to the specific mine or region. For more on the specific localities,...produce attractive emeralds. Zimbabweâs Sandawana mine is noted for small stones (0.05 to 1 ct) of high...far there has been only limited production from mine dumps (N. Kuznetsov, pers. comm., 2000). The most |  | | Journal (article/letter/editorial) | | use . . . . . . . . . . . . . . . . . . . . . Graphite . . . . . . . . . . . . . . . . . . . . . . ....mineralogy of graphite. . . . . . . . . . . . . . . 50.2. Magmatic deposits of graphite . . . . . . ....Structure-bound graphite deposits . . . . . . . . . . . . . . . . 50.4. Sedimentary graphite deposits . ...50.5. Metamorphic graphite deposits . . . . . . . . . . . . . . . . . . 50.6. Graphite supply and use ...Goethite Gold native GoldïŹeldite Gorceixite Goyazite Graphite Gratonite Greenalite Greenockite Gregoryite Greigite | | | Journal (article/letter/editorial) | | use . . . . . . . . . . . . . . . . . . . . . Graphite . . . . . . . . . . . . . . . . . . . . . . ....mineralogy of graphite. . . . . . . . . . . . . . . 50.2. Magmatic deposits of graphite . . . . . . ....Structure-bound graphite deposits . . . . . . . . . . . . . . . . 50.4. Sedimentary graphite deposits . ...50.5. Metamorphic graphite deposits . . . . . . . . . . . . . . . . . . 50.6. Graphite supply and use ...Goethite Gold native GoldïŹeldite Gorceixite Goyazite Graphite Gratonite Greenalite Greenockite Gregoryite Greigite |  | | Journal (article/letter/editorial) | | in which the starting materials are melted in a graphite crucible with melting in air in a platinum crucible...Shannon and Rossman (1992) Locality Lelatema Lualenyi, Jeffrey Unknown Jeffrey Unknown Synthetic Synthetic...Lake Jaco, Synthetic Synthetic Hills, Kenya? Mine, Mine, Mine, Chihuahua, Tanzania Quebec, Quebec, Quebec...rodingite-hosted fluid inclusions in the JM asbestos mine, Asbestos, QuĂ©bec. Geochemical Transactions, 8, |  | | Book | | ancient mine sites from Greek and Roman authors who were not in the gem trade. Fictional mine sources...could also hamper modern efforts in locating ancient mine sources. However, Theophrastus is quite explicit...One thing seems certain, however: the Carthaginian mine source must have been rather extensive, lasting...of exceptionally bright red colours from several mine sites created and maintained these high market values...years later, Agricola described the location of the mine site and said that it was 'five miles from Leitmeritz |  | | Journal (issue) | | Schneider, 1977. sample No. 10 sample No.8: Ruby from Kenya sample No.9: Ruby from Pakistan sample No.7: Ruby...occurrence of the emerald, said to be the Cobra Mine* in South Africa, was recognizable by the totality...discovered at the open-cast site of the Jagersfontein mine in South Africa's Orange Free State in 1893. The...nor has it caused their early demise. The Kollur mine, in the vicinity of Golconda, India, is said to...account of this feldspar and of the Harts Range mine in Northern Territory. SG 2.57, RI 1.520-1.527. |
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