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Coarse Diabase

By Communications and Publishing
Image shows a large gray stone in shade, surrounded by gravel and grass
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Detailed Description

Diabase is a mafic (meaning high in magnesium and iron), igneous rock that usually forms below the Earth’s surface. This particular one has large amounts of augite and labradorite minerals, and comes from the Lucke Quarry, which is southeast of Leesburg, VA.

Sources/Usage

Public Domain.