Quick Answer

A polished finish is built step by step, and every grit stage has a job to do. Use soft resin-bonded diamond pads, run wet, starting at 400–800 grit stage and finishing at 3000 to burnish onyx. Onyx is soft (Mohs 3–4), translucent, and prone to chipping, so never start with coarse metal-bond pads — they cut too aggressively and can eat through the surface.

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Why Onyx Needs Special Care

What matters most in this stage.

• Heat sensitivity: dry burnishing burns onyx rapidly — always burnish wet.
• Softness: onyx scratch marks and wears faster than granite or quartzite.
• Filling: many onyx slabs are resin-filled; aggressive pads can pull the filler out.
• Translucency: over-burnishing can make the stone look washed out or reveal internal fractures.

Miss this step and the gloss will not come up evenly.

The Right Pad Sequence for Onyx

The practical details.

Use diamond white resin floor burnish pads or standard diamond resin burnish pads on a soft backing pad.

Crews that rush this part rarely get a mirror finish.

Pro Tips on Delicate Stone

Key points for the polishing sequence.

• Use a variable-speed grinder and never exceed ~2500 rotations per minute.
• Assess on a scrap piece first — every onyx slab behaves differently.
• Work with the pad level; the edge of a tilted pad digs into soft stone.
• Rinse between grit stages to see the true finish and stop carrying coarse grit stage.

This stage decides how much reflection the floor finally shows.

Frequently Asked Questions

Q: Am I able to polish onyx dry?

A: In short, Not recommended. Onyx overheats and burns rapidly when burnished dry; wet burnishing protects the surface and gives a clearer mirror finish.

Q: What speed should I use?

A: The practical answer is, 1000–2000 rotations per minute on a variable-speed grinder. Higher speeds generate heat that softens and damages onyx.

Q: My onyx has cracks and fissures — will polishing make it worse?

A: For most jobs, It can. Fill cracks with a color-matched epoxy resin before burnishing, and use only soft resin pads with light pressure.

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Conclusion

Follow the grit ladder in order, keep the pads flat, and the gloss builds predictably. Onyx and delicate stones burnish safely with soft resin pads run wet at low speed, starting at 400–800 grit stage and finishing at 3000.