Gemmology
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Cordierite — specimen 0123, photo © NMNHS
Cordierite — specimen 0123, photo © NMNHS

Cordieritespecimen 0123

Origin

East Africa
Tanzania
Cordierite — specimen 0123, locality map
Data

Weight: 0.21 ct; size: 5.07 | 3.09 | 2.16 mm; shape: oval; colour: medium light blue; very slightly greyish; clarity: eye clean; cut: good; treatment: none.
Notes

Very clean specimen; good mixed style cut. Source: Gary Eisenberg, Knoxville, Tennessee.

Other specimens
Cordierite — specimen 0025Cordierite — specimen 0214Cordierite — specimen 0380Cordierite — specimen 0381Cordierite — specimen 0389Cordierite — specimen 0390

More information from ‘Classification’


In thermally metamorphosed argillaceous sediments and regionally metamorphosed schists, gneisses; in mafic igneous rocks and granites (Anthony et al., 2001—2005). The gemstone bears the name iolite.