Sulphides

Sphalerite

  

Group: sulphide

Formula: ZnS

Crystal system: isometric

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Lustre:Adamantine, Resinous

Transparency:Transparent, Translucent

Colour:Yellow, light to dark brown, black, red-brown, colourless, light blue. green

Streak:Pale yellow to brown

Hardness:3½ - 4 on Mohs scale

Tenacity:Brittle

Cleavage:Perfect

Fracture: Conchoidal

Density:3.9 - 4.1 g/cm3 (Measured) 4.096 g/cm3