Assertion: basalt | /r/HasProperty | gray
Facets:
value: usually
type: DEGREE
value: in color
type: OTHER
Source sentences:
text: Basalt is a finely granulated igneous rock, which is usually black or gray in color.
text: Basalt is usually grey to black in colour, but rapidly weathers to brown or rust-red due to oxidation of its mafic (iron-rich) minerals into hematite and other iron oxides and hydroxides.