We also have quartzite and we were very concerned when these marks showed up, specifically if we let wet dishes sit on the counter. We found that these water marks dried up and disappeared within a few hours. Have you found that with yours? Or is this the first time you are seeing these water marks? I also tested a few drops of oil in a very inconspicuous spot and found that it made a mark, but dissipated in a day or so.

ETA: I did talk about my concerns with my KD and she assured me that lighter quartzites have a tendency to do this but that they will not etch or stain like marble.

The oil mark has not gone away. Sometimes the water marks disappear.

There are a number of threads on this forum about stones being sold as quartzite, that are not actually quartzite. Real quartzite does not etch or stain or absorb water and oil like that. However, you have what you have. Regard it the way you would marble. It looks like marble.

Here are a few threads; there are quite a lot of them on this topic:

https://www.houzz.com/discussions/4426353/the-definitive-guide-to-quartzite#n=59

https://www.houzz.com/discussions/2609428/countertop-geology-marble-and-quartzite-and-granite-oh-my#n=157

https://www.houzz.com/discussions/2438427/countertop-geology-part-5-marble-quartzite-and-other-favorites#n=165

I’d contact Daltile. They replaced the countertops for this person In the attached thread. We have quartzite from Daltile but it was not advertised as presealed. It wipes up like glass. Nothing has penetrated it. Our fabricator sealed it after install. https://www.houzz.com/discussions/5582040/quartzite-nightmare#n=83

"I’d appreciate an opinion from a licensed professional who routinely works with quartzite for kitchen applications."

Lisa: I'm a licensed contractor in two states, had my contract for my online column on countertop repairs renewed for four consecutive years, and run a sink replacement business predominantly involving stone.

I doubt your stone is quartzite. Test it please. Karen_mt has some great threads on testing here, but I can't seem to find them. This will have to do.

https://www.houzz.com/activities/user/karin_mt_2/comments

“Karen_mt has some great threads on testing here, but I can't seem to find them.”

@Joseph Corlett, LLC - my post that is 2 posts above yours has 3 links to posts authored by karin_mt.

Thanks everyone for your advice. There are other issues with the installation, like significant cosmetic defects on the stone surface, edge profiles and fissures. We asked Home Depot for a refund, since the first fabricator was incompetent and the second one they referred to us to told us they can’t help as their company is not licensed to work in NC where we live. Home Depot said they can’t give us a refund until they come extract the countertop from our home. However, they have no one to do this work! You can’t make this stuff up! It’s the worst customer experience we’ve ever had. We’ve experienced extremely poor customer service and follow-up from the contractor and the local Home Depot store in Blairsville, Georgia. We are going to file a claim with our credit card company, the BBB and Home Depot corporate, as we’re not confident Home Depot will follow through with the refund.

Remove the oil with a poultice and apply several coats of sealer.

Lisa, please see 'govner's' posts of July 11 and 22, 2019 in this post. They had the same quartzite as yours and Daltile refunded their money. I would contact Daltile as well.

https://www.houzz.com/discussions/5210899/quartzite-countertop-dilemma#24308680

Just to clarify, quartzite can be porous -- or not. So the staining does not mean it's not quartzite. It does mean that the stone is porous and that the sealer isn't doing enough. Either a better sealer or a better stone are needed.

http://usenaturalstone.org/properties-of-quartzite/

Hi, wondering if anyone has experience removing oil stains from quartzite?

we have the Mont Blanc, and almost immediately got stains. the fabricator said they had sealed it twice and that it would not need sealing for 6 months or so, but DAYS after it was installed we got these weird white marks, we got dark rings from oil that was only sitting for a few minutes, and water would mark it after a few minutes as well. The water stains go away after a few hours, but the oil and the weird white stains wont. I want to re seal myself but dont want to seal the stains in. We got this from Daltile and both they and the fabricators have not been much help. I feel very stressed and lost as this was an expensive counter!