1984 Photomicrography Competition

Inclusions of goethite and hematite in Brazilian agate

John I. Koivula

Affiliation
Gemological Institute of America
Carlsbad, California, USA
Technique
Transmitted Light with Reflected Fiber-optic Illumination
Magnification
30x

Colony of Plumatella in water preparation

Pentti J. Alho

Location
Helsinki, Finland
Technique
Rheinberg Illumination
Magnification
16x