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ppl 5*

xpl 5*

ppl can see angle of extinction/inclined extinction = CPX 5*

xpl extinction position 5*

ppl plagioclase matrix 5*

xpl 5*

group                                   pyroxene
system                                  monoclinic
formula                                 (Ca,Mg,Fe,Al)2(Si,Al)2O6
optic                                   biaxial pos
Too-Vee                                 25 - 70¡
relief.1                                high pos
min. index                              1.664  / 1.771
color                                   colorless, green, violet
pleochroism                             no
birefringence.1                         0.018 -0.034
cleavage                                yes
elongation                              no
extinction                              inclined
angle                                   35 - 50¡
alteration                              uralite, serpentine, chlorite, biotite, carbonates
habit.1                                 equant, prismatic, columnar
occurence                               igneous (mafic)
TwoV                                    1 2
relief                                  3 
pleochroism.2                           
birefringence                           5 8 9 10 11 12
cleavage.2                              {110} typical pyroxene cleavage at 87¡