R811 Sample ID R811 • Cabinet X Basalt 7.476cm W x 10.718cm H x 3.13cm D • 296g Sample TypeRockRock QualityIgneousRock TypeExtrusive CompositionMaficTextureColor IndexDark Clast SizeAcid ReactionMohs Hardness 5 The rock is shaped somewhat like a thin half circle, with clear/opaque mineral crystals growing on the top of the rock where there was most likely a gas bubble in the basalt. Description of Mohs scale here