Assertion: onyx | /r/HasProperty | material
Facets:
Source sentences:
text: Onyx is a material that has been described in many ways over the centuries.
text: Were you looking for Onyx, the material or Sarcophagus, the Dyson sphere located at the former site of Onyx?
text: Onyx is one such material – its stiffness and its thermal properties
text: Onyx is a material that has been described in many ways over the centuries.