Are you sure it is from water. We have had a granite countertop in my dh and son's bathroom for years. I would notice wet spots from where my messy boys would splash water or leave a wet washcloth. The spots always dried up and faded after a day or so if I was vigilant about drying up behind them. I had not been great about resealing regularly, but since resealing the water beads up and sits on top of the counter a lot longer. I really hope water doesn't stain granite as I have just spent $$$$ on my new kitchen counters. Maybe one of our experts will have an answer.

Water doesn't stain granite. If that's what was on the countertop and not some other substance.

What did you scrub the "stain" with? You do know that you should only use soap and water on it, or a cleaner marked for granite cleaning - don't you?

the spots only just appeared today. Last night my husband left a couple of washed pans on the island to dry, that's why I'm thinking it must be water. I only use water and microfibers to clean the granite. Should I be contacting the kitchen contractor about the granite? The installers broke the island during installation so the piece on their now, came from a different slab than what is on the other countertops.

Assuming that there is nothing else on the counter - no chemical cleaners or anything that might have snuck onto it - I bet if you leave it alone overnight, the "stain" will be gone in the morning. The installers *may* have neglected to seal the piece in the island - maybe you should check that. That would account for the water "stain", but there again, the mark will likely disappear overnight even if it does need to be sealed.

If the island does need sealing, that isn't a big deal - you could do that yourself.

What kind of granite is it? From what I've read on here, water stains on granite are often because the granite was sealed unnecessarily (not all granites need to be sealed). So the water is marking the sealer rather than the granite itself.

The granite is verde candeias. The other counters have not been staining and because they're new, I've been taking very good care of them.

I am a fabricator.

+1 on the 000 steel wool. we get called several times a year for "stains" that turn out to easily removed mineral deposits.

WARNING: be very careful with rust remover type cleaning agents (like "Iron Out"). The acid in iron out is the only commonly used household cleaning agent that can actually damage (etch) a polished granite surface. A customer once left a rag wet with an iron out solution on her countertop overnight (she was interrupted while cleaning iron stains from her sink) and the granite was damaged by morning.

Water left overnight that dries could leave some mineral residue that should wipe up easily. You would notice just a light outline of where the water dried. A non ammonia glass cleaner should work. Cleaners with a vinegar dilution work well also on mineral deposits. Make sure your surface is acid resistant first.
If the marks or stains you are getting are a whitish spot or hazy type of ghost like mark then that would indicate possibly a sealer has been applied incorrectly.
I don't think the sealer got etched but the water sitting on the sealer may have gotten below the sealer and caused the mark. If a water based sealer was used the white mark once the water evaporates may dry and be gone. With solvent based sealers the mark may stay.
If this is your case call your installer and they will be able to remove the product and with it the marks.
Of course test your stone and do a little research before speaking to them.
If a dense stone has been sealed by an inexperienced worker its possible that some sealer residue is left on the surface of the stone. I would bet the side where you are having no problems may have been sealed by another worker correctly or not sealed.

Verde Candias from brazil is quite dense-In the stone business a true stain(caused by a staining agent) will always be darker than the stone itself.
A lighter stain will indicate an etch mark. Generally there are no exceptions to this rule.
However Verde candias is acid resistant and wont etch from normal household acids. Sealers are impregnating(they live below the surface of the stone) but when left on the surface they will etch.
Do the water test to check porosity by puddling up a palm sized puddle of water and leaving there for 10 or 15 minutes.
Then wipe away -if a dark mark remains the surface is absorbent. The mark will disappear and you will know whether your surface is absorbent or not.
Hope this helps

The masters have spoken. I can add nothing.

There is a dark ring on our months-old granite left where a plastic soap dispenser bottle once sat. I discovered while cleaning the counter a few days ago and removed the bottle, but the stain is still there. We've had other granite countertops in the past and this has never happened before. I will give it a few more days and then contact the installer. Hopefully he can come up with a solution.

Hopefully the spot is where you'd like a hole drilled for a pump soap dispenser and the escutcheon will cover it.

I once rented in an apartment where the bathroom stall was granite. There was one spot where it looked like water had gotten up underneath the top layer of granite and it was perpetually wet right there in only that one spot. It never dried. Some of the other responders seem to think you are referring to a surface-level "stain," but is that what you meant? In my experience the "stain" was not at the surface, but was up underneath and could not be reached, but was extremely visible and dark in that area and stayed wet permanently.

Without seeing a photo I would suggest spraying it with a dry white powder (pull out carpet stain lifter). Could take quite a few applications but it if it's just residue from the soap it will come out. Be sure what you have is granite and not a marble, too many applications will eventually etch the marble. After you need to seal your tops again especially if it's being penetrated by soap.

Thank you all for your help!

"Water doesn't stain granite."

Really?

Who knew?