For small blemishes uses 400 grit.
Wet sand marble countertop.
Allow the sealer to sit on the surface of the marble for up to five minutes.
Start with the coarsest grit sandpaper you have.
Grinding unrepaired cracks will cause the edges to chip creating holes.
In addition polishing grit or marble dust will fill.
Note use 220 when trying to smooth out irregularities.
Mix three tablespoons of soda with one quart of water and apply it on the surface then let air dry for several hours.
If the cultured marble surface still isn t smooth and shiny try wet sanding with 1 000 grit wet dry sandpaper also available at auto supply stores followed by buffing with rubbing and polishing compounds to remove any scratches from the sandpaper.
After washing it with warm water wipe crushed chalk on the countertop rinse again and dry with a chamois cloth.
Wet the surface of the sandpaper and marble.
For anything else start with 600.
Saturate the surface of the marble countertop a second time and wait 30 minutes.
Spray a penetrating stone sealer on the marble countertops until the surface is wet.
Fill a clean spray bottle with plain water and spray a light coating of water over the marble.
By wetting the marble before you sand you ll give the dust something to stick to so it will form a paste rather than flying into the air where you could inhale it.
Wet the surface of the marble with a spray bottle.