Assertion: red beryl | /r/HasProperty | distinguished
Facets:
value: from their difference in refractive index
type: CAUSE
Source sentences:
text: Red beryl has been known to be confused with pezzottaite, a caesium analog of beryl, that has been found in Madagascar and more recently Afghanistan; cut gems of the two varieties can be distinguished from their difference in refractive index, and rough crystals can be easily distinguished by differing crystal systems (pezzottaite trigonal, red beryl hexagonal).