A black variety of cryptocrystalline quartz (chalcedony), with white bands that run parallel. Similar in composition to agate, but the bands in agate are curved & not always parallel. Cryptocrystalline quartz has a hexagonal growth structure, but is too small to see with the naked eye. It grows in a solution of silicon dioxide, instead of outside layer by layer, like quartz with defined points. Onyx is traditionally black with white banding, while Sardonyx is brown/red with white banding. It is also found in white and green. Found all over the world, and has been known since ancient times, Onyx is often carved into cabochons and used in jewelry.

– Associated with the root chakra, the zodiac signs Leo & Capricorn, and vibrates to the number 6.

– Stone of inner strength. Enhances endurance and persistence, enabling one to continue with difficult tasks.
– Helps maintain focus, increasing learning ability & information retention.
– Useful for staying on one’s path, to carry on & to reach one’s highest goals.
– Stone of self mastery. Calms nervousness, anxiety & hot tempers.
– Provides excellent grounding when working with other people’s energy, high energy stones or dangerous situations.

Chemical Formula: SiO₂
Shape: amorphous
Crystal System: trigonal
Habit: massive
Color: black with straight white banding
Streak: white
Luster: waxy, vitreous when polished
Transparency: translucent to opaque
Hardness: 6.5-7 Mohs
Cleavage: none
Fracture: conchoidal
Specific Gravity: 2.6-2.65 g/cm³
Refractive Index: 1.450-1.550