Before you try anything: always speak to a professional before cleaning, treating or applying any product to your stone. Every slab is different, and the wrong product can cause permanent damage. Contact us or a qualified stone restorer first.
Quick answer
Very fine scratches on polished onyx can be reduced with a marble polishing powder; anything you can feel with a fingernail needs a stone restorer to hone it out with progressively finer diamond pads and re-polish. There is no product that hides scratches in stone for long: waxes and "scratch fillers" fill them briefly and wear off.
First, check what you are dealing with
- Grey or dark line: may be a metal mark. Try a cream cleaner first.
- Fine white line, smooth to the touch: a light scratch.
- Line that catches a fingernail: a deep scratch needing honing.
What you need
- Non-scratch cream cleaner
- A stone restorer
Step by step
Rule out metal marks
Rub the line with a non-scratch cream cleaner and a damp cloth. Grey lines from pots and cutlery often disappear completely.
Assess depth
Look at the scratch at a low angle and run a fingernail across it.
Book a professional
Onyx needs a restorer who works with it regularly: it is softer and more fragile than marble and easy to over-polish.
Prevent new ones
Use boards and felt pads under decor, and lift rather than slide heavy items.
What not to use on onyx
- Sandpaper and hardware-store abrasives.
- Coloured waxes or "scratch cover" products, which build up and attract dirt.
- Polishing powder on honed onyx.
When to call a professional
Call a restorer for scratches you can feel, clusters of scratches on an island or table, and anything on onyx. Onyx needs a restorer who works with it regularly: it is softer and more fragile than marble and easy to over-polish.
Understanding scratches on onyx
Onyx is soft and often brittle; the base of a glass can scratch it, and slabs are usually reinforced with resin and mesh on the back.
On polished, often backlit onyx, etches and scratches are visible from far away and light shines through any change in the surface.
Onyx needs a restorer who works with it regularly: it is softer and more fragile than marble and easy to over-polish.
Good to know
Onyx scratches from glassware alone, so backlit bars accumulate fine scratches quickly. A specialist polish removes them.
Stop it happening again
Whether yours is honey, white, green and pink banded onyx, often backlit, repairing it fixes today's mark; protecting it stops the next one. Our clear Stone Protection Film sits over the surface, so acids cannot etch it and liquids cannot soak in, and its self-healing top layer shrugs off fine everyday marks. Onyx is usually polished, so Gloss film is the natural match and keeps its reflective depth. It is installed across Sydney with a 10-year written warranty.
How we protect onyx · Honed vs polished stone · Scratches on every surface