Assertion: chalcedony's hardness | /r/HasProperty | scratched parallel
Facets:
value: to 6.5
type: OTHER
value: to 6
type: OTHER
Source sentences:
text: Hardness is 4- 4.5 (Mohs scale) when scratched parallel to the long axis of the crystal and 6-7 when cut perpendicular to or across the long axis.
text: The hardness of Kyanite is approximately 4.5 when scratched parallel to the long axis of the crystal and approximately 6.5 when scratched perpendicular to or across the long axis.