If you search for quartzite generally you'll see some references to white or gray quartzites used for counters. I haven't seen any silver ones though. Our white/gray quartzite counters will be installed in a couple of weeks.

Sochi I did read your posting with pics of white quartzite and marble. Which one are you using? My concern is the staining. I sprayed a sample with a home store sealer as directions called for. I tested ginger ale, salad dressing, blue berries, hot sauces, etc. I let it sit for 5 to 7 minutes and then wiped. I found that the quartzite absorbed the liquid and left spots. These spots did disappear in about an hour but left a residual mark almost like it etched off the sealer. Those marks will be visible as you walk by the counter. I'm certain this will bother me. I am wondering though if the sealer I used is inferior to a professional sealer that will be used by the installer. Our fabricator is getting us a new sample to retest. I was just curious if anyone has had experience with Silver Quartzite. It's almost like concrete - solid grey in color but once you come up to it you'll see tiny brown specks and some blue also. I think it's very beautiful but unsure of the porosity of the stone.
I added a link to silver quartzite images.

Here is a link that might be useful: silver quartzite images

Wow, that is beautiful, I love it! I wish I had seen some before I made my decision! Alas, it is too late for me.

The quartzites I've read about here seem to stand up very well to testing, but I'm sure it is variable based on the stone. I think the quartzite we are getting (Luce de Luna or Quartzite Bianca) is from South America, so it is possible that an Italian quartzite could be different - but I'm no expert I'm afraid.
Not all sealers are equal either. Most people here use 511 Porous Plus? Do a search and you'll likely find more detailed information on sealants. I might try another sample with a better sealer and see if it improves performance. Good luck!