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Orange-Red to Yellowish Brown Cordierite from Madagascar

Zwaan, J. C. (Hanco) and Pezzotta, Federico and Rossman, George (2016) Orange-Red to Yellowish Brown Cordierite from Madagascar. Journal of Gemmology, 35 (1). pp. 8-9. ISSN 1355-4565.

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Gem-quality cordierite is typically seen as blue material (iolite), showing strong pleochroism in yellow, light blue and dark violet-blue. However, in late 2014 one of the authors (FP) learned about a new occurrence of a much different cordierite, which typically ranged from dark orange-red to yellowish brown. The material is recovered by local miners from weathered residual deposits in southern Madagascar, probably in the Gogogogo area, north of Ampanihy in Tuléar Province. One of the authors (FP) obtained about 120 kg of rough material of mixed quality from the miners over a period of a few months, from which only a few kilograms were suitable for cutting cabochons and faceted stones.

Item Type:Article
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URLURL TypeDescription PublisherArticle
Rossman, George0000-0002-4571-6884
Additional Information:© 2016 Gemmological Association of Great Britain.
Issue or Number:1
Record Number:CaltechAUTHORS:20180423-135408137
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:86014
Deposited By: Tony Diaz
Deposited On:25 Apr 2018 17:51
Last Modified:10 Dec 2020 23:48

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