Vote for your favorite mineral in #MinCup26! - Sphalerite vs. Anorthite Both zinc ore Sphalerite and calcium plagioclase feldspar Anorthite have perfect cleavage that will split cleanly if you hit them with a hammer, but only one can claim a larger split of your votes!
"Ferroan calcite is abundant and is intimately associated with the zeolites. The calcites are various shades of yellow, orange and brown, are translucent to opaque, and occur in a number of spectacular forms such as clubs which sometimes taper to fragile stems providing the point of attachment to the matrix; 'bow-ties'; hemispheres and nodules. The various structures are usually made up of tightly packed fibres which give a silky appearance to the specimen when held in a certain direction. Calcite also occurs as yellowish brown glassy prisms. Simple calcite rhombs are rare, although 'dog-tooth spar' is not uncommon."
Corporation quarries, Clifton Hill, Collingwood, City of Yarra, Victoria, Australia