I’m not familiar with the car key scratch test, but I did run a key down the 3 samples we’re considering, and they all scratched. Super white’s scratch was silver though (could that be a good thing???). I did the lemon test on on 3 as well, and they were all fine.

Super White is not a quartzite so i would rule that one out.

Stones have many different names, If you cannont find anything online chances are it has a different name as well.

Check out some of the threads about Quartzites posted by Karen_mt.

I came across one of her posts a while back, but just read a few more. She's a wealth of knowledge! I also did the glass test, and all 3 of my samples failed. I'm at a loss now. We originally planned on black pearl leathered with white cabinets, but we switched our cabinet color to a dark grey and wanted lighter counter tops. I guess it's back to the drawing board.

Rebekah Sanford, like I suspected this Mar Gris is a marble then; Super White is a dolomite (hard marble), it is pretty hard; harder than Mar Gris.

I recommend you keep looking, don't be in a rush, the stone must talk to you. If what you love is marble, go for it. If you want a stone with more endurance granite or quartzite;

There are grey [true] quartzites in the market like Silver Shadow and others.

I found this online. maybe it will give you the information you need.

https://www.mcgranitecountertops.com/quartzite/

3rd row down shows a color called Mar Gris

Thanks D Old Granite! I'm trying to be patient, but that's not one of my strong points!

Spenard Builders Supply - MC Granite is actually who we're using! They're awesome. Based on the above info, we've decided against Mar Gris.

I found a beautiful piece of granite very similar to viscont white today, but it was a remnant. So, the search continues.