Assertion: zircon | /r/HasProperty | brittle
Facets:
Source sentences:
text: Some zircon, especially gems that have been heat treated, can be brittle.
text: Zircon is a brittle stone, easily broken with a well-placed knock, due to internal stresses in the crystal caused by radiation damage and heat treatment.
text: Although reasonably hard, (rating 6.5 to 7.5 on the Mohs scale), zircon is somewhat brittle and therefore sensitive to knocks and pressure.