group pyroxene
system monoclinic
formula CaFeSi2O6
optic biaxial pos
Too-Vee 25 - 70¡
relief.1 high pos
min. index 1.664 / 1.771
color colorless, gray, brown
pleochroism yes
birefringence.1 0.018 - 0.034
cleavage yes
elongation yes
extinction inclined, symmetrical
angle 35 - 48¡
alteration uralite (amphibole), serpentine, chlorite, biotite
habit.1 prismatic, bladed, acicular
occurence igneous(granitic, volcanic, mafic),metamorphic(medium to high grade, skarn)
TwoV 1 2
relief 3
pleochroism.2 green, blue, brown
birefringence 5 7 8 9 10 11 12
cleavage.2 {110} pyroxene cleavage at 87¡