Chapter 23 Gem deposits of Myanmarстатья из журнала
Аннотация: The aim of this chapter is to review the locations, mineralogy and briefly the origins of the major gem deposits in Myanmar. Myanmar is fortunate in containing world-class gem deposits, such as the finest pigeon's-blood-coloured ruby from the Mogok Stone Tract in Mandalay Division, the Mong Hsu ruby deposit in Shan State and imperial coloured jadeite jade from Kachin State (Fig. 23.1). For the purposes of description the gemstone deposits in Myanmar are classified into: (1) primary hard-rock deposits in which the gemstones are hosted in the rocks in which they were crystallized or in their weathered products; and (2) secondary deposits in which the gemstones have been weathered out of their original (primary) host rock, transported and deposited as placer deposits in alluvial sediments.
Fig. 23.1.
Locations of the Jade Mine, Mogok Stone Tract and Mong Hsu areas and the tectonic zones in Myanmar: 1, the Arakan (Rakhine) coastal strip; 2, Indo-Myanmar Ranges; 3, Western Inner-Myanmar Tertiary Basin; 4, Central Volcanic Belt (Central Volcanic Line); 5, Eastern Inner-Myanmar Tertiary Basin; 6, Shan-Tenasserim Massif (map modified after Bender 1983; Khin Zaw 1989, 1990; Khin Zaw et al. 2015). Small white circles represent extinct or dormant Tertiary volcanoes.
Examples of the primary-type gems are ruby in marble (Mogok, Mong Hsu and Sagyin), sapphire in syenite pegmatite, syenite and nepheline syenite (Mogok) and jadeite in serpentinized peridotite (Tawmaw). Other precious gemstones from primary deposits include spinel in marble (Mogok), peridot in dunite/peridotite (Mogok), topaz, aquamarine, tourmaline, quartz, etc. in pegmatite (Mogok, Mong Hsu and Momeik) and kyanite in quartzite (Moehnyin).
Rare gemstones are often found in primary gem deposits in the Mogok Stone Tract and include johachidolite and hackmanite from pegmatites, painite from leucogranite and skarn, pollucite, petalite, phenakite, pezzottaite, monazite, danburite, jeremejevite and hambergite from pegmatites in the Momeik area. …
Год издания: 2017
Издательство: Zoological Society of London
Источник: Geological Society London Memoirs
Ключевые слова: Mineralogy and Gemology Studies, Geological and Geochemical Analysis, Geology and Paleoclimatology Research
Открытый доступ: closed
Том: 48
Выпуск: 1
Страницы: 497–529