Species: Eilat Stone
Mohs Hardness: 5 to 6 out of 10
Color: Semitranslucent to opaque, blue to green with mottled appearance. Usually a combination of chrysocolla and malachite, but can also contain turquoise, copper and other minerals.
RI: Depending on where you test:
Malachite: Blinking from around 1.66 to OTL
Birefringence: Malachite areas may have birefringence of 0.250
Spectrum: Not diagnostic
SG: Typically 2.80 to 3.20 (Varies when copper minerals are present)