Assertion: beryllium | /r/HasProperty | a steel gray
Facets:
Source sentences:
text: Beryllium is a steel gray and hard metal that is brittle at room temperature and has a close-packed hexagonal crystal structure.
text: , Beryllium is a steel grey, strong, light-weight yet brittle, alkaline earth metal , that is primarily used as a hardening agent in alloys (most notably, beryllium copper ).
text: Beryllium is a steel-gray metal that is quite brittle at room temperature, and its chemical properties somewhat resemble those of aluminum.