Garnets typically forms 12 or 24 sided crystals in metamorphic rocks, and also igneous rocks. They range in color from red to pruple, green, yellow, brown, white, and clear; hardness 6.5 - 7.5; no cleavage; conchoidal fracture. 
     

This specimen shows a 12 sided (Dodechahedral) crystal.

 

 

 

Garnets typically forms 12 or 24 sided crystals, and range in color from red to pruple, green, yellow, brown, white, and clear; hardness 6.5 - 7.5; no cleavage; conchoidal fracture.
     

This specimen is a porphoroblast (a mass of crystal looking like an igneous porphyry, but produced by metamorphism) of red garnet surrounded by amphibole (rock = amphibilite). The mass may look like it has mineral cleavage running from left to right, but it is metamorphic rock cleavage.