Sphalerite

==Sphalerite is a mineral that is the chief of Zinc. When in crystal form, it mostly have Iron. The colour of Sphalerite is yellow, brown, gray and gray-black. Sphalerite can be used into gemstones. The hardness is 3.5- 4, the fracture is uneven to conchoidal, the cleavage is perfect, the luster is adamantine, resinous, greasy and the streak is brownish white and pale yellow.==