

1st Place, 1984
John I. Koivula
Gemological Institute of America
Santa Monica, California, USA
Inclusions of goethite and hematite in Brazilian agate (30x)
Transmitted Light with Reflected Fiber-optic Illumination


John I. Koivula
Gemological Institute of America
Santa Monica, California, USA
Inclusions of goethite and hematite in Brazilian agate (30x)
Transmitted Light with Reflected Fiber-optic Illumination