MN402 Sample ID MN402 • Cabinet F Sphalerite 3.96748cm W x 1.80594cm H x 3.28168cm D • 28g Sample TypeMineralColorBlack with red undertonesLusterResinous to Glasslike StreakLight BrownCleavage/FractureRhombohedral Cleavage/Uneven FractureSpecific Gravity4.66 Geographic Location/DateCumberland England Mohs Hardness 5 Small Ore of Zinc. Black to the visible eye but red when scratched. Groundmass of resinous rock. It has Tetragonal crystals that are opaque. Description of Mohs scale here