2 cts 9x8 mm Loose Mexican Fire Opal Cabochon for sale x561

 We sell rough and cut gemstones, offering a wide range of rough gemstones for specimen-cabbing-facet and beautiful cut stones ready for your mount..Either for a new piece of jewelry or replacing a stone in an existing piece of jewelry.We offer thousands of lots, all with individual photos, what you see in the photo is what you will receive. Tommysrocks, an internet only business since 2002, giving our internet customers 100% of our attention. 

Opal (hydrous silicon dioxide)  
Color: Colorless, yellow, orange, red and brown.

Mohs hardness: 5-6.5

Refractive index: 1.44-1.46

Critical angle: 43.5°

Specific gravity: 1.9-2.23

Cleavage: None

Fracture: Conchoidal, brittle, splintery.

Dispersion: None

Heat sensitivity: High to moderate

Pleochroism: None

Birefringence (double refraction): None

Crystal structure: Amorphous

Polishing: Cerium on most common polishing laps.

Comments: Care should be taken when dopping to prevent damage to the stone by thermal shock.  Stones that display opalescent fire are usually better to cut as cabochons.