Geology Home Page
Roger Weller, geology instructor
Chemical Group: silicate-pyroxene
Chemical Formula: CaMgSi2O6
Color: white, yellowish, pale gray, pale green, dark green, black, colorless
Luster: vitreous Transparency: transparent to translucent
Hardness: 5 to 6
Specific Gravity: 3.2 to 3.38
Cleavage: imperfect prismatic cleavage (110); angles of 870 and 930.
Crystal Forms: Monoclinic
Crystal prismatic with square or 8-sided cross section.
Mineral Associations: Diopside is commonly a contact metamorphic mineral
in crystalline limestones. It is associated with tremolite, scapolite, idocrase,
garnet, and sphene.
Identifying Characteristics: crystal form, light color, and angles between cleavage surfaces.
Uses: If transparent, it is cut as a gemstone.
Occurrences: U.S.S.R, Austia, Switzerland, Italy, Sweden: in the USA in Connecticut and New York
Toxicity: when-swallowed- when inhaled-