cross-posted from: https://lemmy.world/post/46766835

Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of clay minerals and silt-sized particles of other minerals, especially quartz and calcite. It is characterized by fissility, the tendency to split into thin layers less than 1 centimetre (0.39 in) in thickness, and is the most common sedimentary rock.

Photographer: Chris Woodrich

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