PERIDOT FROM THE CENTRAL HIGHLANDS OF VIETNAM: PROPERTIES, ORIGIN, AND FORMATION

Vietnam is an important source of peridot for the international gem market. Gemological and geochemical characteristics of Vietnamese peridot from the Central Highlands are similar to those noted for other localities originating from xenoliths in alkaline basalts. Thi s peridot was derived from a spinel lherzolite source and appeared to form at temperatures between 910° and 980°C and an assumed pressure of 2.0 ± 0.5 GPa, corresponding to a depth of around 60 km. Peridot is a yellowish green to green gem variety of the mineral olivine. It is found as nodules in igneous rocks, occasionally as crystals in veins (in Myanmar and Pakistan) or inside meteorites. The main sources are peridotite xenoliths in alkaline basalts and serpentinized dunites (Shen et al., 2011). Commercially important sources are Zabargad, Egypt; San Carlos, Arizona (United States); Myanmar; China; Kohistan, Pakistan; Vietnam; Ethiopia; and Tanzania. Many studies have focused on the characteristics of peridot from these sources (Gübelin, 1981; Koivula, 19 81; Stockton and Manson, 1983; Koivula and Fryer, 1986; Fuhrbach, 1992; Sinkankas et al., 1992; Nassau, 1994; Kane, 2004; Adamo et al., 2009). Jan and Khan (1996) showed the gemological and chemical properties of peridot from Sapat Valley in Kohistan and suggested that its mineralization is related to post-tectonic hydrothermal activity. Bouilhol et al. (2012) proposed that the mineralization of peridot in Kohistan precipitated from subduction-derived fluids. Until now, though, geochemical characteristics, genesis, and P-T formation conditions of gem-quality peridot have received little attention

Title: PERIDOT FROM THE CENTRAL HIGHLANDS OF VIETNAM: PROPERTIES, ORIGIN, AND FORMATION
Authors: Hauzenberger, Christoph;
Nguyen, Ngoc Khoi
Nguyen, Thi Minh Thuyet
Keywords: Gemological
Geochemical characteristics
Vietnam
Issue Date: 2016
Publisher: H. : ĐHQGHN
Citation: ISIKNOWLEDGE
Abstract: Vietnam is an important source of peridot for the international gem market. Gemological and geochemical characteristics of Vietnamese peridot from the Central Highlands are similar to those noted for other localities originating from xenoliths in alkaline basalts. Thi s peridot was derived from a spinel lherzolite source and appeared to form at temperatures between 910° and 980°C and an assumed pressure of 2.0 ± 0.5 GPa, corresponding to a depth of around 60 km. Peridot is a yellowish green to green gem variety of the mineral olivine. It is found as nodules in igneous rocks, occasionally as crystals in veins (in Myanmar and Pakistan) or inside meteorites. The main sources are peridotite xenoliths in alkaline basalts and serpentinized dunites (Shen et al., 2011). Commercially important sources are Zabargad, Egypt; San Carlos, Arizona (United States); Myanmar; China; Kohistan, Pakistan; Vietnam; Ethiopia; and Tanzania. Many studies have focused on the characteristics of peridot from these sources (Gübelin, 1981; Koivula, 19 81; Stockton and Manson, 1983; Koivula and Fryer, 1986; Fuhrbach, 1992; Sinkankas et al., 1992; Nassau, 1994; Kane, 2004; Adamo et al., 2009). Jan and Khan (1996) showed the gemological and chemical properties of peridot from Sapat Valley in Kohistan and suggested that its mineralization is related to post-tectonic hydrothermal activity. Bouilhol et al. (2012) proposed that the mineralization of peridot in Kohistan precipitated from subduction-derived fluids. Until now, though, geochemical characteristics, genesis, and P-T formation conditions of gem-quality peridot have received little attention
Description: GEMS & GEMOLOGY Volume: 52 Issue: 3 Pages: 276-287 ; TNS06377
URI: http://repository.vnu.edu.vn/handle/VNU_123/26715
Appears in Collections:Bài báo của ĐHQGHN trong Web of Science

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