1988 Photomicrography Competition
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12th Place
Inclusions of pyrolusite and limonite in a polished slab of Brazilian agate
John I. Koivula
- Affiliation
- Gemological Institute of America
Carlsbad, California, USA
- Technique
- Brightfield
- Magnifaction
- 14
12th Place
Inclusions of pyrolusite and limonite in a polished slab of Brazilian agate