If the ammonia and water mix doesn t do the trick acetone a solvent used in products such as nail polish remover can help lift the stain and get into the craggy pore of marble.
White marble stain removal.
Vinegar chlorox peroxide comet.
Rub the powder onto the stone with a damp cloth or by using a buffing pad with a low speed power drill.
Each one of these above stains have a unique method of removal.
I ended up taking 200 grit wet or dry sand paper and wet buffing the whole top down.
Once the stain has been removed wet the surface with clear water and sprinkle on marble polishing powder available from a hardware or lapidary store or your local stone dealer.
I have seen two approaches mentioned on line to remove stains from cultured marble.
Then i went over it with 1000 grit wet dry.
This is a material made from a porous solid and a solvent some sort of liquid to form a paste type material that has the consistence of cake icing or peanut butter.
Water stains can be easily removed from marble.
Whether you re working to get stains out of an old neglected marble mantlepiece or rust stains out of a newer marble shower the method remains the same.
Avoid using abrasives which may damage the surface.
Unfortunately rust stains are the most difficult of stains to remove from marble.
There also are light grayish stains around the drains.
Method of stain removal.
If you try these methods and still do not have success contact a professional to assess the problem.
Apply it to the stain and cover it with plastic for 24 hours.
Cultured marble a mix of marble powder and a polyester resin requires a gentle touch when it comes to cleaning.
None of these things worked in my yellow stain.
To clean stained marble mix baking soda and water until it s a thick paste.
Other than the stains the cultured marble is in very good condition and the original gel coat still is relatively shiny.
You can either use regular marble cleaner or try removing the stain using grade 0000 steel wool.
Most of them can be removed with a marble poultice.
Use a damp cloth to wipe away the mixture repeating the process if the stain is still there.
For regular marble maintenance wipe up spills with a warm damp cloth and dry it with a cloth.
Instead use a soft cloth and liquid based stain removers such as vinegar or a mild soap and water to treat many kinds of stains.
Pouring the acetone concentration into or onto the stain probably won t be effective though.