|Figure 7-2. High-magnification view of an aragonite layer (A) between two calcite layers (C). Note straight edges of radiating crystal boundaries (red arrows) within the aragonite. Also note relatively straight and non-euhedral crystal teminations of the underlying calcite layer (green arrow), suggesting latest calcite precipitation from a relatively thin water film that did support development of pointed crystal terminations. A
lower-magnification view shows alternation of these aragonite and calcite layers.
Photomicrograph was taken in plane-polarized light; field of view is 0.33 mm wide. Drotsky's Cave, Ngamiland, Botswana; Stalagmite BDS1 (DS87); thin section BDS9-10. Sample collected by Drs. George Brook and John Cooke.
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