Onyx
Sardonyx gemstone
A variety of Onyx
What is Onyx?
Healing Properties
Onyx is considered an emotional healing stone that is often used to aid the grieving process and alleviate stress. This stone is associated with strength and stamina as well as the building of self-confidence and self-control. Wear it as jewelry, use it for meditation, or carry it close to the body.
Optical Properties
- Refractive Index
- 1.530-1.543
- Birefringence
- 0.004
- Pleochroism
- None
- Optical Character
- Biaxial positive
Discover Values
Market Value Factors
Pricing varies for every rock and mineral, so use these universal factors to gauge Onyx before comparing listings or appraisals.
Size & Weight
Larger, intact specimens usually command higher prices.
Rarity & Demand
Scarce material or popular varieties sell at a premium.
Condition & Finish
Chips, repairs, and heavy wear lower value; clean prep helps.
Treatment & Provenance
Untreated specimens with documented locality are prized.
Onyx Localities Map
See where Onyx is found with a localities map, collecting zones, and geology context. Generate a sample map preview below.
More Images
Quick Facts
Physical Properties
- Streak
- White
Chemical Properties
- Chemical Formula
- SiO2
- Elements
- Si, O
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