How to clean Onyx
Cleaning onyx comes down to one rule: pH-neutral cleaners and soft tools. Onyx is a banded calcite stone, often translucent enough to backlight. It is soft, brittle, and reactive — best treated as a feature material, not a workhorse.
What you'll need
- • pH-neutral stone cleaner (or a few drops of dish soap in warm water as a backup)
- • Two soft microfiber cloths
- • Warm distilled water
- • Soft bristled brush for textured surfaces
Step-by-step
- 1Dust or sweep loose debris off the surface — grit acts like sandpaper under a cloth.
- 2Spray the stone cleaner directly on the surface (not the cloth) and let it dwell 15–30 seconds.
- 3Wipe with a damp microfiber in light overlapping passes — never scrub.
- 4Rinse with a clean cloth and warm distilled water to remove cleaner residue.
- 5Buff dry with the second microfiber to prevent water spots.
- 6Stone-safe pH-neutral cleaner; dry immediately.
Do not use
- Vinegar, lemon, or any acidic cleaner — Acid etches onyx permanently — leaves dull, lighter spots.
- Bleach — Strips sealer and can discolor the surface.
- Abrasive scrub pads or scouring powder — Scratches the finish.
- All-purpose sprays not labeled stone-safe — Most contain solvents or acids that damage natural stone.
When to call a pro
Almost all onyx repairs should be done by a stone restoration pro.
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