Assertion: color tourmaline | /r/HasAspect | a hardness of 7 to 7.5
Facets:
value: on the mohs’ scale
type: OTHER
Source sentences:
text: Bi-color tourmaline gemstones are excellently suited for wearing and are uncomplicated to care for, since all bi-color tourmalines have a hardness of 7 to 7.5 on the Mohs’ scale.