Brown and Flame-Coloured Stones
Hardness. Specific Gravity.
Andalusite    7-1/2 3.204 Diamond 10 3.502-3.564 Garnets (various) 6-1/2-7-1/2 3.40-4.50 Hyacinth (a form of Zircon), 7-1/2 4.70-4.88 Quartz (smoke coloured) 7 2.670 Tourmaline 7-1/4 3.100 Zircon (Hyacinth) 7-1/2 4.70-4.88
