Here's the story.

Two years ago we gut reno'd our upstairs bath. The tile is a Calacatta harlequin. About a week ago, I got out of the shower, looked down and noticed that all of the tile around the toilet had turned gray--the way marble looks when it's wet. I had seen this happen maybe once before, but the grayness seemed to subside. It is clearly not the result of anybody making a mess, and the center of the circle is definitely the drain stack. The gray area extends about a foot in every direction from there.

A plumber stopped by and suggested before he pulls and re-seats the toilet, we check to see if it's condensation. The temps did suddenly drop around here last week and the water coming in is noticeably colder. We creatively taped plastic wrap around some parts of the toilet and floor to check for condensation, but didn't really seem to find any.

Oddities:
-- The toilet is still very firmly seated.
-- No ceiling stains in the room below.
-- No water of any kind visible
-- The tile stays gray--normally, this marble whitens again if it gets wet and dries out
-- We now almost never use this toilet until it's fixed, yet as I said, the marble stays gray

The soonest the plumber can come back is Thursday or Friday, and I've decided to play it safe and just have him pull the toilet and put in a new wax ring.

Of course it's very easy to spill a little water when moving the toilet, so we may not be able to tell what's going for sure.

If it's not a broken wax ring (in a two year old toilet!) what could it be?

And why is the marble remaining gray? It's a very even gray, nothing suggesting a nasty stain.

Do you think a poultice will improve the look?

The new plumber installed a spacer, a new wax ring and re-seated the toilet.

Issue is, the gray tile isn't going anywhere. I obviously cannot lift the toilet up on a daily basis to check for leaks. Am I wrong to expect the tile to whiten up again? It has a sealer on it, so I imagine that impedes evaporation a bit.

I don't mind making a poultice to take up any stain--I know how to do that and it usually works. My concern is whether the continuing gray patch means a continuing leak, or if it's just a leftover from the original leak.