R879 Sample ID R879 • Cabinet B Rhyolite 5cm W x 3.9cm H x 4.4cm D • 170g Sample TypeRockRock QualityIgneousRock TypeExtrusive CompositionFelsicTextureColor IndexReddish Clast SizeAcid ReactionMohs Hardness 6 pink red and grey swirling bands in layers Description of Mohs scale here