A translucent, generally layered, cryptocrystalline calcite.
All onyx will acid etch when exposed to acidic foods such as lemons or tomatoes. Most onyx has a moderate absorption rating and will stain when exposed to oil and highly-pigmented liquids. All onyx has a very low abrasion resistance rating; it will scratch, stun and crack. All onyx has naturally occurring cracks and fissures.
- Onyx must be handled with extreme care in both fabrication and installation.
- Onyx is suitable for interior wall applications, not for floors. Onyx is sometimes used on vanities and other non-food service countertops; in these instances, the end user must be made aware of its acid sensitivity and fragility.
- Always use a neutral detergent or professional stone cleaners to clean onyx.
- Expect to see factory-repaired cracks and fissures. The quality of the repair is dependent upon the factory of origin, the fabricator of the stone and the installer.