R766 Sample ID R766 • Cabinet C Chert 4.364cm W x 11.318cm H x 3.587cm D • 236g Sample TypeRockRock QualitySedimentaryRock TypeChemical CompositionSilicaGrain SizeFineGrain ShapeN/A Grain SortingWell sortedAcid ReactionNoMohs Hardness 7 It is a rock that was cut open to look at the crystalline structure inside the rock. The crystalline structure shows layering having occurred. The rock is light tan in color. Description of Mohs scale here