Crazing is small, hairline cracks that form around a cultured marble sink's drain. After years of exposure to hot and cold water, the cracks appear on older marble basins and worsen over time if left untreated. Advances in the chemistry of cultured marble has almost completely eliminated this issue, but it is still present on older pieces. You can remove crazing from your cultured marble sink basin without causing further damage or scratches.
Clean the marble crazing with a mixture of 1 tablespoon mild liquid dish soap and 5 cups lukewarm water. Dampen a soft cloth with the mixture and wipe down the affected area to remove any soap scum, dirt or debris. Rinse away the soapy solution with warm water and dry with a chamois cloth.
Combine the tinted marble epoxy according to the package directions. Stir a small amount of the tint into the epoxy and match it against the marble's color. Add more tint until the desired color is achieved.
Apply the tinted marble epoxy to the crazing with a small paintbrush. Use slight pressure to work the epoxy deep into the cracked cultured marble.
Allow the marble epoxy to cure according to the package directions. Remove any excess epoxy with a razor blade after it is dry.
Smooth the epoxy with 220-grit sandpaper. Gently work the sandpaper over the repair until it is flush with the surrounding marble basin.
Wipe away the sanding dust with a tack cloth before restoring the marble with a polishing compound. Work the polishing compound into the repaired area with a soft cloth.