Assertion: bloodstone's appearance | /r/HasProperty | due
Facets:
value: to other substances
type: CAUSE
value: to oxidation of its surface
type: CAUSE
Source sentences:
text: The brown external appearance is due to oxidation of its surface.
text: The banded appearance is due to other substances which may include quartz (amethyst or rock crystal), chalcedony (jasper, onyx, carnelian) and etc.