R750 Sample ID R750 • Cabinet C Limestone 10.99cm W x 12.501cm H x 5.867cm D • 744g Sample TypeRockRock QualitySedimentaryRock TypeClastic CompositionShell fragmentsGrain SizeCoarseGrain ShapeN/A Grain SortingPoorly sortedAcid ReactionYesMohs Hardness 3 It is shaped like a rectangular chunk of shells, broken shells and such somewhat cemented together. It is yellow in color and some white from the shells as well. Description of Mohs scale here