TY - JOUR
T1 - Characterisation and Genesis of Sapphires from the Yenya-U Area, Thabeikkyin Township, Mandalay Region, Myanmar
AU - Phyu, Khin Mar
AU - Zaw, Khin
AU - Mernagh, Terrence Patrick
AU - Aung, Thu Zar
N1 - Publisher Copyright:
© 2021 Gem-A (The Gemmological Association of Great Britain)
PY - 2021
Y1 - 2021
N2 - The Yenya-U area in the Mandalay region of central Myanmar hosts two primary sapphire deposits, at Kyauk-tagar and Kyar-gaung. The sapphires form disseminated crystals within syenite pegmatite and nepheline syenite, respectively. Kyar-gaung is a source of relatively large crystals (up to 12 g) that are translucent to opaque, while Kyauk-tagar produces fine-quality vivid-blue sapphires in smaller sizes (up to 0.4 g). Alluvial deposits in the region yield high-quality sapphires of various colours (including colourless, yellow, purple, pink, greenish blue and blue), as well as quartz, topaz, spinel, garnet, zircon, tourmaline and fluorite. The studied Yenya-U sapphires contained solid inclusions of albite, biotite, graphite, melanophlogite and diaspore. In addition, pennantite is reported here for the first time as an inclusion in corundum. CO2-rich fluid inclusions were commonly observed in most of the sapphires. Trace-element analyses of the sapphires are consistent with a metamorphicmetasomatic origin, mostly accompanied by desilicification processes.
AB - The Yenya-U area in the Mandalay region of central Myanmar hosts two primary sapphire deposits, at Kyauk-tagar and Kyar-gaung. The sapphires form disseminated crystals within syenite pegmatite and nepheline syenite, respectively. Kyar-gaung is a source of relatively large crystals (up to 12 g) that are translucent to opaque, while Kyauk-tagar produces fine-quality vivid-blue sapphires in smaller sizes (up to 0.4 g). Alluvial deposits in the region yield high-quality sapphires of various colours (including colourless, yellow, purple, pink, greenish blue and blue), as well as quartz, topaz, spinel, garnet, zircon, tourmaline and fluorite. The studied Yenya-U sapphires contained solid inclusions of albite, biotite, graphite, melanophlogite and diaspore. In addition, pennantite is reported here for the first time as an inclusion in corundum. CO2-rich fluid inclusions were commonly observed in most of the sapphires. Trace-element analyses of the sapphires are consistent with a metamorphicmetasomatic origin, mostly accompanied by desilicification processes.
UR - http://www.scopus.com/inward/record.url?scp=85124028764&partnerID=8YFLogxK
U2 - 10.15506/JoG.2021.37.8.802
DO - 10.15506/JoG.2021.37.8.802
M3 - Article
SN - 1355-4565
VL - 37
SP - 802
EP - 815
JO - Journal of Gemmology
JF - Journal of Gemmology
IS - 8
ER -