| Spinels from Sri Lanka 54 The Spinels of Mahenge, Tanzania In Search of Cobalt Blue Spinel in Vietnam...InColor Summer 2019 A 7.13-ct spinel from Mahenge, Tanzania. Cover image: Prangpak Ruahong, Nomads. 40...million and China's Hong Kong Special Administrative Region (SAR) with US$30.8 million, said the ministry's...ancient Kingdom of Balascia, related to Badakhshan, a region spanning parts of present-day Afghanistan and Tajikistan...are found in Tajikistan, Myanmar, Vietnam and Tanzania (Yavorskyy and Hughes, 2010; Giuliani et al., |
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Cairncross, Bruce (2019) Minerals & Gemstones of East Africa - Burundi, Kenya, Rwanda, Tanzania and Uganda. Penguin Random House. |
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 |
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Wu, Jinlin, Sun, Xueying, Ma, Hong, Ning, Peiying, Tang, Na, Ding, Ting, Li, Huihuang, Zhang, Tianyang, Ma, Ying (2023) Purple-Violet Gem Spinel from Tanzania and Myanmar: Inclusion, Spectroscopy, Chemistry, and Color. Minerals, 13 (2) 226 doi:10.3390/min13020226 |
Journal (article/letter/editorial) |
| minerals Article Purple-Violet Gem Spinel from Tanzania and Myanmar: Inclusion, Spectroscopy, Chemistry...com.cn Abstract: Purple-violet gem spinels from Tanzania and Myanmar have been investigated for their gemological...phlogopite, and forsterite in Tanzanian spinel and magnesite, apatite, baddeleyite, anhydrite, pyroxene, and...hue angle and lightless of purple spinels from Tanzania. However, due to the relatively stable content...study are of a limited number of samples from Tanzania and Myanmar. Citation: Wu, J.; Sun, X.; Ma, H |
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Giuliani, Gaston, Fallick, Anthony E., Boyce, Adrian J., Pardieu, Vincent, Pham, Van Long (2017) Pink and Red Spinels In Marble: Trace Elements, Oxygen Isotopes, and Sources. The Canadian Mineralogist, 55 (4) 743-761 doi:10.3749/canmin.1700009 |
Journal (article/letter/editorial) |
| from Paigutan in Nepal, Kiswila and Ipanko in Tanzania, Pamreso in Kenya, Mogok in Myanmar, and An Phu...in Tajikistan, Myanmar, Vietnam (Fig. 1A), and Tanzania (Yavorskyy & Hughes 2010). Occurrences are known...phlogopite 6 magnesiohornblende white schist and magnesite marble hosting sapphirine (Spr), gem spinel, amphibole...m. The paragenesis is completed by enstatite, magnesite, Frich phlogopite, pyrrhotite, pyrite, rutile...Kenya, the Pamreso spinel occurrence, in the Voi region, is spatially associated with tsavorite deposits |
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Keller, Peter C (1992) Gemstones of East Africa. Geoscience Press, Inc. |
Book |
| gemological wealth of East Africa. This unique region encompasses ·what may be the world's richest gem...gemologist and geologist, Dr. Peter Keller. Kenya and Tanzania are revealed in their full mineralogical splendor...chrome tourmaline are widely identified with the region. ( continuedon backflap) ♦ ♦ ♦ ♦ ♦ ~...Conclusion 11 Chapter 2. Diamond Deposits of Tanzania 15 Location 16 Geology 18 Mining 20 Properties...Northern Province, Tanzania 28 Ruby and Sapphire from Umba, Tanga Province, Tanzania 32 Sapphire from Kenya |
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Mercier, A., Debat, P., Saul, John M. (1999) Exotic origin of the ruby deposits of the Mangari area in SE Kenya. Ore Geology Reviews, 14 (2) 83-104 doi:10.1016/s0169-1368(99)00002-5 |
Journal (article/letter/editorial) |
| work concerns primary ruby deposits in Kenya and Tanzania especially those of the Mangari area inside the...Park ŽFig. 1. in SE Kenya. East Africa ŽKenya–Tanzania. is endowed with primary corundum deposits ŽHughes...rubyrsapphire deposit of Umba River in northeast Tanzania by Solesbury Ž1967., and studies of the ruby deposits...In SE Kenya, and apparently continuing into NE Tanzania, most Žor all. of the known primary gemcorundum...best known, for its deposit of blue sapphire and magnesite, is located at Kinyiki Hill just north of Mtito |
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Muhongo, S., Kröner, A., Wallbrecher, E., Tuisku, P., Hauzenberger, C., Sommer, H. (2001) Cross-Section Through the Mozambique Belt of East Africa and Implications for Gondwana Assembly. Gondwana Research, 4 (4) 709-710 doi:10.1016/s1342-937x(05)70506-2 |
Journal (article/letter/editorial) |
| Department of Geology, University of Dar-es-Salaam, Tanzania, E-mail: muhongo@udsm.ac.tz lnstitut fur Geowissenschaften...the best exposures are in East-Central, and NE-Tanzania (Uluguru-, Pare-Usambara mountain ranges); and...granulite-facies rocks of eastern and north eastern Tanzania (Muhongo, et al., 2001). Gneisses (ca. 800°C/10...Ophiolite Complex in the Kenya/ Ethiopia border region. The original gabbro in this complex crystallized...rocks is in South Pare, around the old Chambogo Magnesite Mine (04'08.356 S/37' 48.894 E), where gabbros |
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(2020) The Journal of Gemmology Vol. 37 (4) Gem-A |
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| ‘caramel spice’ variegated opal, yellow-green magnesite sold as ‘lemon chrysoprase’ and amethyst with...west of Sakoany village in the Mahajanga (Majunga) region on the north-western coast of Madagascar, near...(605 nm) was somewhat shifted towards the blue region and it lacked Figure 1: This 4.22 ct celestine...inclusions in the ruby permitted the features in this region to be fully resolved. Corundum is anhydrous and...Because vesuvianite absorbs strongly in the mid-IR region of the spectrum, even minute inclusions can give |
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(2022, September) Rock & Gem Vol. 52 (9) Beckett Media |
Journal (issue) |
| Richard Gross & Pam Freeman 44 BUSINESS PROFILE: MAHENGE GEMS BRINGS SPINEL TO THE WORLD By Amy Grisak ...is the Saranovski Mine, in Sarany, in the Urals region of Russia. WWW.ROCKNGEM.COM | SEPTEMBER 2022 19...dyes them blue. The porous minerals howlite and magnesite have achieved dubious fame for the ease b they...howlite or magnesite. How to tell? Look for white spots since some portions of howlite and magnesite are less...Slovakia; South Africa; Spain; Sweden; Switzerland; Tanzania; United Kingdom; United States WWW.ROCKNGEM.COM |
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(2011, December) Gems & Gemology Vol. 47 (4) Gemological Institute of America |
Journal (issue) |
| 316 Gem News International Chondrodite from Tanzania • Blue dolomite from Colombia • Fluorite from...Culture Yellowish Green Diopside and Tremolite from Tanzania Polymer-Impregnated Turquoise Fall 2007 The Transformation...GIA Laboratory Rubies and Sapphires from Winza, Tanzania The Wittelsbach Blue Spring 2009 The French Blue...Polymer-Filled Aquamarine Yellow-Green Haüyne from Tanzania Aquamarine from Masino-Bregaglia Massif, Italy...Chrysoprase and Prase Opal from Haneti, Central Tanzania Demantoid from Val Malenco, Italy Spring 2010 |
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(2016) The Journal of Gemmology Vol. 35 (1) Gem-A |
Journal (issue) |
| pyrite mixture from Colombia|Garnet from Mahenge, Tanzania |
Grandidierite from Madagascar |
Lalique quartz...danburite; heat treatment of spinel from Mahenge, Tanzania; cobalt diffusion-treated spinel; a challenging...Garnet from Mahenge, Tanzania The Mahenge area in the Morogoro region of south-central Tanzania is a well-known...sold as ‘Mahenge Malaya’. He obtained the rough material in mid-December 2015 in Arusha, Tanzania. Consisting...79 and 6.84 ct, these faceted garnets from Mahenge, Tanzania, are unusually large for this new find. Courtesy |
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(2010, September) Gems & Gemology Vol. 46 (3) Gemological Institute of America |
Journal (issue) |
| of Aurora Gems; (6) a 9.15 ct ruby from Winza, Tanzania, courtesy of Hakimi & Sons; (7) a 14.80 ct “golden”...Africa, and its interest in the Williamson mine of Tanzania. Soon after the Cullinan deal went though (July...Weldon, 2009). One new source of corundum, Winza in Tanzania, began yielding some fine-quality ruby in 2007...with the opening of a new mine in the Nova Era region and technological developments at established mines...licensed to mine tanzanite at Block C in Merelani, Tanzania. This high-security screen enclosure (designed |
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(2016, September) Geobulletin Vol. 59 (3) Geological Society of South Africa |
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| loosened within a dendritic fracture development of a region but system that was generated during the early...anorthosite. The overwhelming consensus was magnesite veins and dyke-like protuberance of platinum-...of continents, ultramafic magmatism, historical region and also improved their own understanding of and...acquire the Mahenge of 5.33% copper, both at a 2% cut-off. Liandu graphite project in Tanzania. The project...Epanko project and Gold Black Rock Mining’s Mahenge project. A mineralised trend about 1.6 km in strike |
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(2015, Spring) Gems & Gemology Vol. 51 (1) Gemological Institute of America |
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| sequence. B lue spinels are mined in Sri Lanka, Tanzania, Myanmar, Pakistan, and Vietnam (Shigley and Stockton...spectra, in the violet to blue region (400– 500 nm) and in the red region (670–700 nm). We also observed...large transmission window in the blue to violet region, and a smaller one in the red. The bands at 371...and 500 nm (in the blue region) and between 670 and 900 nm (in the red region). This explains the pink...Compact fluorescent light emits more in the blue region than in the red, and therefore the spinel appears |
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(2022) The Journal of Gemmology Vol. 38 (6) Gem-A |
Journal (issue) |
| Central Madagascar | Spessartine from Engare Naibor, Tanzania |
Update on Colourless HPHT-grown Synthetic Diamonds...emerald deposit was discovered in 2021 in the Chitral region of north-western Pakistan. Following an earlier...the past decade, the Numbi area in the South Kivu region of the Democratic Republic of the Congo (DRC) has...Athiliwewa) in Sri Lanka, Umba and Tunduru in Tanzania, and Bekily in Madagascar (Schmetzer & Bernhardt...change came from a deposit near the border of Tanzania and Kenya (Sun et al. 2017). In all cases, V has |
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(1915) Bulletin of the Imperial Institute Vol. 13 (1) The Imperial Institute |
Journal (issue) |
| of the globe, and throughout the Mediter ranean region, including Spain, Crete, and Sicily. The worm is...There have been small planting experiments in Mahenge, Bagamoyo, and Pangani, which, however, are too...natives regarding methods of collection (chiefly in Mahenge, Iringa, and Tabora), and the avoidance of adulteration...chiefly in the districts of Muansa, Bagamoyo, Morogoro, Mohoro, Kil wa, and Lindi, in spite of much damage...weather, in Bagamoyo, Kilwa, and Pangani ; from Morogoro 116 BULLETIN OF THE IMPERIAL INSTITUTE there |
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(1995) The Journal of Gemmology Vol. 24 (8) Gem-A |
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| responsible for optical effects are described. As yet the region has not yielded a corundum crystal large enough...plant matter or dead animals can penetrate this region (Gubelin, 1987) unless forced by some external...intruded sand grain which somehow had penetrated the region between the shell and the shellbuilding ectoderm...cabochon-cut examples of the following gems from Tanzania and Kenya: almandine, apatite, aquamarine, beryl... asterism, cabochon, inclusions. Introduction Tanzania and Kenya now contribute significantly to the |
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(2012, Fall/Autumn) InColor 21. International Colored Gemstones Association |
Journal (issue) |
| Rare ‘Haüyne’ Ethical Mining and Fair Trade Tanzania: Ethical Initiatives and CSR Synergies Jewelry...simply dyed magnesite. One way that dyed magnesite is marketed is to call it turquoise magnesite. Since relatively...relatively few people have heard of magnesite, many may believe they are buying a unique and more valuable...Zhuang Myanmar President Thein Sein. Autonomous Region. More than 90 companies from Myanmar displayed...largest buyer of tanzanite in the world, has visited Tanzania for the first time. Gad, who reportedly buys 70 |
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(2011, Spring) InColor 16. International Colored Gemstones Association |
Journal (issue) |
| the tsavorite project in the Manyara region of northeast Tanzania, about 20 kilometers from its tanzanite...following similar actions taken by South Africa and Tanzania. The new firm is expected to be up and running...Attapeu.) This is the infamous “Golden Triangle” region, where the borders of Thailand, Laos, and Myanmar...so-called ”emerald belt” in the Itabira-Nova Era region (Figure 2). History The discovery of emeralds...emerald belt is located in the Santa Maria de Itabira region in the southwestern corner of the map. www.gemstone |
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(2002) The Journal of Gemmology Vol. 28 (3) Gem-A |
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| crucible, the seed is positioned in the coolest region of the furnace. SiC, vaporized from the feed powder...to the fact that the samples were faceted from a region of the crystal at some distance from the seed where...displayed rather featureless IR spectra in the region of 2400-3400 cm 1 , and four peaks only were present...3.28 ct does not exhibit a peak located in the region of 3310 c m 1 present in all the tested samples...minerals are not stable within the diamond stability region and thus are rather unlikely to occur as inclusions |
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(2016) The Journal of Gemmology Vol. 35 (4) Gem-A |
Journal (issue) |
| northwestern Pakistan|‘Black’ axinite |
Beryl from Tanzania with phenakite inclusions |
Clinohumite from Vietnam |
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Morgan, W. T. W. (1969) East Africa: its people and resources (1st ed.) Oxford University Press, Nairobi. |
Book (edition) |
| Settlement. 177 15 AGRICULTURE AND LAND TENURE IN TANZANIA by A. HAMERSLEY, m.b.e., b.sc.(agric.) Agriculturalist...Conservator of Forests. 209 18 FORESTRY IN TANZANIA by G. J. KILEO, b.sc. Director of Forestry, Ministry...rocks of the Mozambique Belt. 4a Olduvai Gorge, Tanzania. Pleistocene lake beds and Lemagrut Mountain,...with Pinus radiata in hill country near Mbeya, Tanzania. 6b Log of mahogany, Khaya anthotheca, Budongo...(Isoberlinia-Brachystegia) woodland near Tabora, Tanzania. 9a Semi-desert vegetation. Acacia reficiens subsp |
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Morgan, W. T. W. (1972) East Africa: its people and resources (2nd ed.) Oxford University Press, Nairobi. |
Book (edition) |
| Agriculture. 15 AGRICULTURE AND LAND TENURE IN TANZANIA by A. HAMERSLEY, M.B.£., B.SC.(AGRIC.) ; Agriculturalist...Chief Conservator of Forests. 18 FORESTRY IN TANZANIA by G. J. KILEO, 215 B.sc. Director of Forestry...rocks of the Mozambique Belt. 4a Olduvai Gorge, Tanzania. Pleistocene lake beds and Lemagrut Mountain,...with Pinus radiata in hill country near Mbeya, Tanzania. 6b Log of mahogany, Khaya anthotheca, Budongo...(Julbernardia-Brachystegia) woodland near Tabora, Tanzania. 9a Semi-desert vegetation. Acacia reficiens subsp |
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(1993, January) Gems & Gemology Vol. 29 (4) Gemological Institute of America |
Journal (issue) |
| than the as-grown sample. The broad absorption region between 600 and 800 n m causes the green component...HPHT-treated sample exhibits less absorption in the region where there was "total absorption" for the as-grown...the transmission "window" in the greenish yellow region of the spectrum (at about 560 nm) and, hence, the...toward the ultraviolet and the weak broad absorption region centered at about 700 nnl (evident in spectra B...peak heights of the absorptions in the "nitrogen region" (approximately 1344 to 1000 cm-1)are equal to |
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Dill, Harald G. (2010) The “chessboard” classification scheme of mineral deposits: Mineralogy and geology from aluminum to zirconium. Earth-Science Reviews, 100 (1) 1-420 doi:10.1016/j.earscirev.2009.10.011 |
Journal (article/letter/editorial) |
| Mineral Chemical composition Line Maghemite Magnesite Magnetite Magnetite/vanadiferous Malachite Malayaite...the Alpine region, and (3) Mid-Triassic to early Jurassic extension in the extra-Alpine region. Isotope...deposits embedded within sedimentary series (magnesite, borate) or they form sediments by themselves...make a contribution to the cultural heritage of a region and may successfully be used in exploration (Mascaro...two years. The economic potential of a particular region or mining camp can be deduced from the economic |
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