Mohs Hardness: 6.5 to 7.5 out of 10
Color: Orange, brownish orange, yellowish orange or red orange. Always has an orange component and never shows any purple.
RI: 1.810 (+0.004 / -0.020)
SR/DR/AGG: SR, often with ADR
Clarity Type: Type II
Spectrum: Bands at 412, 424 & 432nm, which sometimes merge to form a cutoff. Bands at 505, 527 & 575nm.
SG: 4.15 (+0.05 / - 0.03)