How to Repair a Deep Scratch in Cultured Marble

Apply a car polishing compound such as 3M's Ultrafine, Auto Glym's Super Resin Polish or Turtle Wax to the scratch and the surrounding area. Car polishing compound is made of a very fine grit suspended in a non-toxic paste such as resin or wax. It will smooth out the edges of the scratch and help level it out with the rest of the counter. Squeeze it from the tube directly onto the counter, and rub it in slightly using a soft cloth until it reaches all areas of the scratch and the area around it.

Rub hard at the edges of the scratch using wet/dry sandpaper. Pour a small amount of water into the compound and continue rubbing both the scratch and the area around it until they are flush or nearly flush with one another. Rinse well with water.

Apply more car refinishing compound to the treated area. Fit a buffing pad onto the end of a variable speed drill and begin buffing the area in a circular motion to even out the finish of the top. Rinse the top well. Stop buffing when the area is completely smooth to the touch.

Apply a coat of Gel-Gloss to the entire counter to give it a high gloss finish and help protect it from further scratching. Rub the gel coat in with a soft cloth using a circular motion and allow it to dry completely. Gel-Gloss is the same product applied at the factory to the cultured marble. It is made of a petroleum base suspended in an aerosol along with propane, butane, silica and water. Hold it at arm's length as you spray to avoid getting it near your eyes.