Physical Properties Of Quartzite

Mohs hardness: 7.

Density: 2.64 g/cm³ – 2.71 g/cm³

Optical characteristics: Anisotropic aggregate.

Refractive index: 1.544 – 1.533, often 1.54 by spot testing.

Birefringence: Not measurable.

Ultraviolet fluorescence: Generally none; for quartzite containing chromium mica: none to weak, grayish-green or red.

Absorption spectrum: Not characteristic; for quartzite containing chromium mica: may show absorption bands at 682 nm and 649 nm.

Dye treatment: Can be dyed in various colors; microscopic examination reveals dye distribution between grains. Green dyed quartzite shows an absorption band at 650 nm.