On Mar 27, 11:52*am, gcotterl wrote:
How would I sand the integral sink in a 20-year-old cultured marble
vanity top? *Also, how would I remove grey (or black) lines in the
bottom of the sink surrounding the pop-up drain?

Its probably mold, let laundry bleach soak it for maybe 10 minutes, it
might help and wont hurt.