R865

Sample ID R865 • Cabinet D

Mud-Cracks in Sandstone

25cm W x 15cm H x 3cm D • 1120g
Sample TypeRockRock QualitySedimentaryRock Type
CompositionGrain SizeFineGrain ShapeRounded
Grain SortingWell sortedAcid ReactionMohs Hardness 4

This specimen preserves a network of mud cracks formed as fine sediment dried and contracted at the surface. Subsequent burial and lithification transformed the original mud into sandstone, retaining the polygonal fracture pattern as a clear record of periodic exposure and drying in a shallow depositional setting.