1. xpl quartz x5
1. xpl quartz x5
2. ppl quartz x5
3. ppl granitic quartz x5
4. xpl granitic quartz x5
group silica
system triagonal
formula SiO2
optic uniaxial pos
Too-Vee 0¡
relief.1 low pos
min. index 1.544 / 1.553
color colorless
pleochroism no
birefringence.1 0.009
cleavage no seen, poor cleavage {1011} and {1010}
elongation yes
extinction undulatory
angle 0¡
alteration not readily altered
habit.1 equant, granular, prismatic
occurence igneous, metamorphic, sedimentary, hydrothermal
TwoV
relief 1
pleochroism.2
birefringence 1 3 4
cleavage.2 (not seen in thin section)