Dark Stain on Marble Countertop
Marble Stain Around Kitchen Sink
My kitchen countertops are honed "Michael Angelo" marble (white with gray and taupe markings).
About a year ago a dark stain appeared by the sink. I don't know what caused the marble stain.
It happened pretty suddenly. I'm thinking something my cleaning lady or a friend spilled (I was out of town for a week).
It has darkened a bit with time and even seems that it may be spreading. Looking at the edge around the sink it appears as if it goes all the way through the marble (3/4" thick).
I have read on your site and others about using bleach or peroxide, which I was going to try, but thought I would contact you first for any other insights.
Good thinking to get some concrete advice about cleaning marble first. Experimenting is risky
. Often people just start trying different products or methods. This can be risking as many products could cause further damage marble.
Bleach and hydrogen peroxide are both good examples. For the record, we have never recommended using these for regular cleaning. In fact, the opposite. Common generic cleaners
like bleach, vinegar, and ammonia are popular and effective for many cleaning projects around the house. Just keep these away from marble. All will etch (corrode) marble and dull the surface.
Really, most brand-name cleaners are too harsh for marble as well.
In general, using marble-specific cleaners only
is the smart bet.
Sometimes hydrogen peroxide is used to remove certain types of marble stains with a special process, but this is done knowing there
is no other way and you will have to deal with any etching later.
Now you have honed marble, so any etching will not be as noticeable, but it still could be. But more to the point
, marble stains are caused when a substance gets into the pores of the stone. You can't remove them by surface cleaning.
Neither bleach nor hydrogen peroxide nor any other cleaning product will get the stain out just by scrubbing.
You may see some improvement with standard cleaning, however, it almost certainly won't completely remove the stain... and it may leave an undesirable etch mark. I recommend
you follow the steps outlined in the Removing Stains Manual
for granite and marble maintenance.
The procedure varies depending on what actually caused the stain. You said you didn't know, but the manual contains instructions for nearly every type of stain including those where you don't know what caused the marble stain.To make things really simple
you can use the Marble Stain Removal Poultice
. It's pre-formulated with instructions and easy to apply.
The stain may be full thickness of the slab, but the staining substance may have just spilled over the edge and caused a stain on the edge as well. Hopefully, that is the case.
A full-thickness stain typically indicates something absorbing from underneath (like the adhesive used to install the countertop). Such stains are extremely difficult to remove.
The stain in the photo does not appear to be glue stain, but it could be if it appeared within days after the marble kitchen countertop was first installed.