Rainbow Stain on granite around sink
Just curious if anyone has seen or heard of this. We have Impala Blue granite that was sealed upon installation 2 1/2 years ago. Our 4 windows go right down to the countertop, so we have a lot of natural light in our kitchen - which we love, except.... when it comes to keeping the countertops clean - EVERYTHING shows during the day (not as much at night) and I find the granite very unforgiving and hard to keep clean and streak free. Unfortunately we do have hard water, and any water that does dry on the counters ends up leaving a white stain. Luckily those stains do dissapear once they are wiped down with water and dried with a towel. I try very very very hard to constantly wipe down the water that gets splashed on the granite around the sink, but with 3 boys.....you know how that goes!!
My question is whether or not anyone has experienced a "rainbow" stain, which I have all around my sink. Funny, you only see it during the daylight and only when the sun does NOT shine directly on the granite. I called my fabricator last summer who came out to my house to see the granite, but had never heard or seen this problem. He was thinking that maybe it was even from the plumber when they installed the faucet because the biggest stain is right at the base of the faucet. After researching and coming up with nothing, he gave me a number of a stone doctor - but I have yet to call him, hoping someone here might be able to give my some insight. The only thing I can think of is that water is somehow trapped in the granite and giving that rainbow effect. Blue Impala has a very low absorption rate (.05-.15), and one that I didn't think needed to be sealed every year. When they came out last summer he said that it should absolutely be sealed every 6 months - but they do seal everything. If I were to leave a wet sponge on the counter for 10 minutes - it does not leave a dark spot and I have never had a problem with oil stains.
However, I also have a lot of small dark rings on my granite, especially above my dishwasher. I have a seam above my dishwasher and they had to come back 6 months after installation and repolish the stone about 1 foot on either side of the seam because during the day, you could see that this area on either side of the seam was much lighter than the rest. I imagine that these rings too are water stains, but after a year, I would think that it would finally dry up. So perhaps I do need to seal this stone - but wanted to find out if I can remove this rainbow stain and dark circles before I do.
You may be wondering why I have waited so long to get this fixed....I had a few issues with the installation - the area around the seam for one (because of course I was being way too picky and had to call them out a few times...) and I was furious when they never asked what reveal I wanted and assumed that I would want the negative reveal (which the overhang is way too much and I lose valuable sink space in the smaller sink of my double sink) even though I gave them the Franke template that calls for a positive reveal....Bottom line though, I never knew that I should be the one to ask or tell so I blame myself for not researching that (clearly I found GW way too late!) I have had some other issues with my kitchen too, which are a bit embarrassing so although I have read thousands and thousands of entries, I have never had the nerve to answer one or ask a question.
But today is a new day! I am so sorry I have made this much longer than I did and I am hoping that I have made some sense. Any insight at all would be just great.