Brown Spots On Cultured Marble Shower Floor

by Sofia T.

QUESTION:

I am having a problem with little brown spots on my shower floor. They look like little rust spots. There is no pattern they are just random. Its not just four or five, there are several. It seems to be getting worse. They are smaller than an eraser on a pencil. Larger than the pencil lead on a regular pencil. Thanks.

ANSWER:

You say "cultured" marble. This is not real stone. It's basically a plastic and feels that way. It won't be tiled... it will be a solid piece... in fact your whole shower may be seamless.

If you indeed do have cultured marble, then I have no idea what is happening. We do not deal in cultured marble and cannot offer any real expertise regarding this product.

If actually you have real marble (tiled, feels like stone not plastic) then the brown spots could be from iron deposits (often found in white marbles) rusting through.

Not a good sign in a shower floor, because it usually means that water is under the tiles. Water under tiles will not dry out. The marble absorbs the water. The water rusts the iron and is carried to the surface with the absorbing water causing a yellow/orange/brown stain.

Water will get under tiles due to cracked or broken grout or simply from a poor installation.

This will not occur from water on the surface unless the iron deposit is also on the surface.

To fix you need to let it dry out completely, fill in any cracks or voids and/or you may have to rip out and replace the floor. Even if you removed the stains, they would simply return until you fixed the source of water.

If a little grout repair solves the water problem, then You'll find complete step-by-step instructions for removing rust stains in the Removing Stains Manual.

Good Luck,
Ryan

P.S. Get all the facts, answers, explanations and simple solutions with step-by-step instructions for any issue, problem or question with our Granite & Marble Maintenance Manuals.

I highly recommend Stone Care Pro Products to maintain all your marble, stone and granite countertops and floors in optimal condition. I've used other good products (Stone Tech, Miracle) but found Stone Care Pro is the most reliable and effective.