| Roman Empire (Part 1) Cobalt-bearing Spinel from Tanzania Nephrite Jade from Washington State, USA Copper...2022 Presentations Cobalt-bearing Spinel from Tanzania Nephrite Jade from Washingto n State, USA Copper...Cobalt-bearing Blue Spinel from Lukande, near Mahenge, Tanzania By Michael S. Krzemnicki, Alex Leuenberger...the Ambatofinandrahna area of the Amoron’i Mania region in central Madagascar, where it was extracted from...iron-bearing phases mostly come from the Siberian region of Russia (Eaton-Magaña et al. 2019). To our knowledge |
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(2019, Summer) InColor 43. International Colored Gemstones Association |
Journal (issue) |
| 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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(2016) The Journal of Gemmology Vol. 35 (2) Gem-A |
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| Turkey|Polymerfilled star enstatite from Norway |
Garnet mining in Tanzania |
Kyanite from Pakistan |
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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...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...Keywords: purple-violet spinel; inclusion; chemistry; Tanzania; Myanmar Ning, P.; Tang, N.; Ding, T.; Li, H |
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Maaskant, P., Coolen, J. J. M. M. M., Burke, E. A. J. (1980) Hibonite and coexisting zoisite and clinozoisite in a calc-silicate granulite from southern Tanzania. Mineralogical Magazine, 43 (332) 995-1003 doi:10.1180/minmag.1980.043.332.07 |
Journal (article/letter/editorial) |
| clinozoisite in a calc-silicate granulite from southern Tanzania P. MAASKANT, J. J. M. M. M. COOLEN, AND E. A....rocks in the Furua Granulite Complex in southern Tanzania. The mineral forms yellowish-brown lath-shaped...mineral in the Furua Granulite Complex in southern Tanzania. This complex forms a part of the five Quarter...Commerce and Industry of Tanzania. The complex is situated south-west of Mahenge in the northern parts of...granulite-facies metamorphics is characteristic. In Tanzania these granulites form a discontinuous, roughly |
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(2020) The Journal of Gemmology Vol. 37 (4) Gem-A |
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| 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...vesuvianite showed total absorption corresponded to the region of the compound band structure in the 2.19 ct ruby |
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(2021, Spring) Gems & Gemology Vol. 57 (1) Gemological Institute of America |
Journal (issue) |
| tributed throughout the central Indo-Pacific region (Southgate and Lucas, 2008). As with other mollusks...distributed throughout the tropical Indo-Pacific region. 16 INTERNAL FEATURES OF NATURAL PEARLS FROM...distributed throughout the tropical Indo-Pacific region (Jeong et al., 2018; Atlas of Living Australia...Pakistan. Other notable spinel sources are Sri Lanka, Tanzania, and Tajikistan. Inclusions found in spinel often...1, p. 58. ——— (1995) Lab Notes: Spinel, with högbomite(?) inclusions. G&G, Vol. 31, No. 4, p. 272. Johnson |
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(2012, Spring) InColor 19. International Colored Gemstones Association |
Journal (issue) |
| eventually craze, the material from the Wollo Province region is considerably more stable. Francesco Mazzero... Most notably, the newer deposits in the Wollo region are testing out to be much more durable than those...treatments is logical as all of the opal from this region is termed hydrophane. Hydrophane has the ability...ruby production (Image 1) between Kenya (52%), Tanzania (28%) and Madagascar (9%), in addition to 42%...spinel producers are Burma, Sri Lanka, Tajikistan, Tanzania, Madagascar and Vietnam. The T he determination |
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(2022) The Journal of Gemmology Vol. 38 (7) Gem-A |
Journal (issue) |
| The mining areas are distributed across a wide region extending from south-western to east-central Nigeria...deposit that is reportedly situated in the Calabar region of southeastern Nigeria. Calabar is located in...tourmaline-bearing pegmatites are widespread in this region, where they are hosted by basement rocks of the...obtained a parcel of rough tourmaline from the Calabar region that weighed 470 g. It consisted of broken pieces...Figure 3: This map of the Banjarmasin–Martapura region of South Kalimantan shows the location of the diamond |
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(2009, July) Gems & Gemology Vol. 45 (2) Gemological Institute of America |
Journal (issue) |
| “Sugarcane Emerald” from Brazil • Orange kyanite from Tanzania • Rare optical phenomenon in play-of-color opal...Dona Dirlam wrote part of her 1992 “Gem Wealth of _Tanzania_” article sitting at my backyard patio table, while...gemological occurrence of pegmatitic gems in the region, as well as research. Based on his decade of experience...Dirlam et al. surveyed the colored stone wealth of Tanzania. Adolph Peretti and coauthors provided the authoritative...~300 nm and absorbed strongly in parts of the IR region (specifically the range 7000–20000 nm). The smaller |
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(2012) The Journal of Gemmology Vol. 33 (1-4) Gem-A |
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| d-electrons and no electronic transitions in the visible region, Mg2+ would normally not be considered to be a...emeralds of Colombia and the Cordillera Oriental region are the result of tectonic-hydrothermal precipitation...of the sub-surface dynamics of the Campos Verdes region has shown distinct similarities to the emerald...in the Copperbelt Province of Zambia. The Ndola region consists of a complex series of pegmatite dykes...Although rare, similar spinels are known from Tanzania, Sri Lanka and Madagascar (e.g. see Modern Jeweler) |
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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 |
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| Hewettite Hibonite Hinsdalite Hocartite Hochschildite Högbomite Hollandite Hollingworthite Holmquistite H.G...the Alpine region, and (3) Mid-Triassic to early Jurassic extension in the extra-Alpine region. Isotope...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...about 50% of them concentrated in the Steelpoort region of the eastern Bushveld Complex. Stratiform deposits |
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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) |
| Hewettite Hibonite Hinsdalite Hocartite Hochschildite Högbomite Hollandite Hollingworthite Holmquistite H.G...the Alpine region, and (3) Mid-Triassic to early Jurassic extension in the extra-Alpine region. Isotope...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...about 50% of them concentrated in the Steelpoort region of the eastern Bushveld Complex. Stratiform deposits |
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