Well, I would be hesitant to spend $$$ on a slab(s) that I can't test. Slab yards have different names for the same type of stone - so, it's difficult to know exactly what you are buying.

Also, there have been several threads re: issues related to whiter quartzites.

" The slab yards I've been to don't give out samples so I can't test it at home. "

Find another slab yard. They can call the stone anything they want as there are no standards. You must do your due diligence and test it yourself.