Its Mohs hardness is 3.5 and it has a specific gravity of 1.88 to 1.90. Optically it is uniaxial negative with indices of refraction of nω = 1.507 and nε = 1.468.
Its Mohs hardness is 3.5 and its density falls within the range of 1.88 to 1.90. In terms of optical behavior, it displays uniaxial negative properties with refractive indices of nω = 1.507 and nε = 1.468.