Assertion: tourmaline's color | /r/HasProperty | secondary minerals
Facets:
value: mostly
type: DEGREE
Source sentences:
text: These minerals are silicates of aluminum, magnesium, and iron, with water; color, usually green; powder, white; luster, earthy or pearly; H = 1 to 3; G = 2.65 to 2,78, Chlorites are mostly secondary minerals, being formed by the alteration of such minerals as biotite, pyroxene, hornblende, etc.