Assertion: tourmaline's color | /r/HasProperty | pleochroism
Facets:
Source sentences:
text: Luster Vitreous Diaphaneity Transparent to translucent to nearly opaque Cleavage Indistinct Mohs Hardness 7 to 7.5 Specific Gravity 2.8 to 3.3 Diagnostic Properties Lack of visible cleavage, prismatic crystals with rounded triangular cross-sections that are often striated, vibrant colors, pleochroism.