Quartz
Epidote
Epidote in PP light Epidote in XP light Off-center biaxial optic axis figure of epidote Negative biaxial optic axis figure of Epidote
Topaz
Topaz in PP light Topaz in XP light Off-center optic axis figure of topaz Positive off-center optic axis figure of topaz
Clinozoisite
Clinozoisite in PP light Clinozoisite in XP light Off-center optic axis figure of clinozoisite Positive off-center optic axis figure of clinozoisite
Kyanite
Kyanite in PP light Kyanite in XP light Obtuse bisectrix interference figure of kyanite
Corundum
Corundum in PP light Corundum in XP light Off-center uniaxial interference figure of Corundum Negative uniaxial interference figure