Answer
For ceramic sinks, clean first. Only test very fine wet sanding, starting around 1000, on minor marks.
Why it happens
Many marks on ceramic are surface transfer marks, but real scratches in glaze are hard to remove evenly.
Recommended grit
Start with cleaning first. For minor surface marks, test 1000, 1500, then 2000 wet in a hidden spot.
Wet or dry
Wet.
Success check
Surface transfer marks are reduced without dulling the glaze.
What to do
- Clean the sink thoroughly first.
- Test a hidden area before sanding the visible surface.
- Wet sand very lightly with 1000, then 1500 and 2000.
- Stop if the glaze starts to look uneven.
Avoid: Do not use coarse grit on glazed ceramic.