Assertion: cassiterite | /r/HasProperty | main ore of tin
Facets:
Source sentences:
text: Although cassiterite is a common mineral, being the main ore of tin, it's crystals are usually black or opaque brown and of no use as a gemstone.
text: Although cassiterite is a common mineral being the main ore of tin
text: Although cassiterite is a common mineral being the main ore of tin
text: Although cassiterite is a common mineral being the main ore of tin