Mohs Hardness: 7 to 7.5 out of 10
Color: Strong color zoning in varying combinations of blues, greens, and reds often combined with alternating colorless layers.
RI: 1.624 to 1.644 (+/-0.005)
Birefringence: Usually 0.018 to 0.020
Clarity Type: Type III
Optic Character: Uniaxial negative
Pleochroism: Usually medium to strong, but can vary.
Spectrum: Often not diagnostic
SG: 3.06 (+0.20 / -0.06)
Routine Treatments: Heating
Additional Enhancements: N/A