Ruby Jack Sphalerite From Illinois- Collectors Piece, Home Décor, Gift

Ruby Jack Sphalerite From Illinois- Collectors Piece, Home Décor, Gift

Weight 235g
Size 13.5cm by 5cm
Thickness 2cm

This Piece is from an old collection

Sphalerite is zinc sulphide and commonly associated with galena in a wide variety of geological settings. Its is popular with mineral collectors for its diverse crystalline form and wide variety of colours. Old mining terms include zinc blende, black jack and ruby jack.

Colour is strongly influenced by iron content with the high iron black variety referred to as marmatite. The very low iron variety which tends to a pale green gemmy translucent colour is referred to as cleiophane. Ruby jack as the name implies refers to the red variety. Minor amounts of manganese and cadmium also influence colour. Finely banded pale brown sphalerite usually intergrown with galena and marcasite bands are referred to as schalenblende which looks a little like tree growth rings.