Assertion: cryolite's hardness | /r/HasAspect | low volatility
Facets:
value: very
type: DEGREE
Source sentences:
text: As corundum is very hard (Mohs hardness 9), has a high melting point of 2,045 °C (3,713 °F), has very low volatility, is chemically inert, and a good electrical insulator, it is often used in abrasives (such as toothpaste), as a refractory material, and in cermanics, as well as being the starting material for the electrolytic production of aluminium metal.