Switch the 120 grit sandpaper pad out for a 320 grit sandpaper pad.
What grit for marble.
If the marble is thick enough it might be worth starting with an 80 or 50 grit with a belt sander belt glued to a flat board and going from there through the grits you ve already done.
I guarantee you that you ll be using 120 grit 220 400 500 600 and over 1 000 grit.
Seal the marble if desired.
Grit sizes march through the double digits triple digits and beyond.
In addition polishing grit or marble dust will fill the crack and redistribute over the surface during the next step scratching rather than polishing the surface.
After going over the entire surface with 120 grit sandpaper repeat with 300 grit sandpaper then 600 grit.
Wipe the marble with a damp sponge to remove sanding dust.
It s a pain but if there s enough by way of thickness good meaning non scarred or cracked marble it can be worth it.
This will require using a wet sanding process to achieve the desired results.
Step 7 dampen a clean sponge with water and rinse the sanding dust off the marble countertop repeating as many times as it takes to remove any.
Repeat sanding the marble countertop in the same way as the previous step misting the surface with water to minimize abrasion marks.
The process starts by using a coarse grit paper and cutting away a fine layer of the stone to remove the scratches or saw blade marks.