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. https://resolver.caltech.edu/CaltechAUTHORS:20180423-135408137
![]() |
PDF
- Published Version
See Usage Policy. 324Kb |
Use this Persistent URL to link to this item: https://resolver.caltech.edu/CaltechAUTHORS:20180423-135408137
Abstract
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 | ||||||
---|---|---|---|---|---|---|---|
Related URLs: |
| ||||||
ORCID: |
| ||||||
Additional Information: | © 2016 Gemmological Association of Great Britain. | ||||||
Issue or Number: | 1 | ||||||
Record Number: | CaltechAUTHORS:20180423-135408137 | ||||||
Persistent URL: | https://resolver.caltech.edu/CaltechAUTHORS:20180423-135408137 | ||||||
Usage Policy: | No commercial reproduction, distribution, display or performance rights in this work are provided. | ||||||
ID Code: | 86014 | ||||||
Collection: | CaltechAUTHORS | ||||||
Deposited By: | Tony Diaz | ||||||
Deposited On: | 25 Apr 2018 17:51 | ||||||
Last Modified: | 10 Dec 2020 23:48 |
Repository Staff Only: item control page