Image: Coal ball thin section1

Description: An unstained thin section of a coal ball from Ohio, United States of America. Calcite can be seen in the plant stem. The microscope magnification was at 50x with plain, polarised light.
Title: Coal ball thin section1
Credit: http://spectrum.troy.edu/~barwood/coal_ball_thin_section_50x.htm
Author: Henry L. Barwood
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