Make sure it's a mortar rated for your climate and exterior use (read the lebels!) AND make sure water can't puddle on the stones or mortar joints by slanting the stones towards the edge of the walkway. As you have seen, as soon as there's a crack, the freeze-thaw cycles bust it up.

We have Quartzite Bianca and had our fabricator test it (ketchup/lime juice/oil) prior to installation and no stains or etches. Unfortunately, after installation, turns out it etches with water. The issue is the resin applied at the quarry (all stone over the past decade has resin applied, mostly for color enhancement) is reacting to acids. You don't think of water being an acid, but it can be depending on the pH. Technically, what etches is a reaction between calcite in the stone (e.g., marble, limestone, travertine) and an acid. Since quartzite does not contain calcite.. etching is caused by the reaction between the resin and the acid which explains why two people with the same stone experience different things re: etching. Depends on the quarry and resin used. I've removed the etching with baking soda, which also means water is not etching the stone, but the surface.. Your fabricator can also rebuff the stone to get the etches off. Won't cure the long-term problem, but can get rid of what etching you currently have. As to sealers.. once I read about people with this stone having oil stains, I researched sealers. I was told silicone-based sealers do a great job repelling water, but attract oil based stains, so I switched to a product by Stone Products (www.superiorstone.com) which is a flouropolymer--a smaller molecule than silicone which means it fills the voids better and does not attract oil stains.

I have fantasy brown and I also like dolce vita quartzite. [dolce vita slab[(https://www.houzz.com/products/dolce-vita-quartzite-prvw-vr~5056980) [dolce vita quartzite[(https://www.houzz.com/photos/dolce-vita-quartzite-phbr0lbl-bl~l_43655)

Beautiful material, but it almost looks like two different pieces of stone! Because of this, you could end up with two sections of your countertop that don’t match at all. Are you prepared for this? Make sure that you have all the details about how your countertop layout will be placed on the slab, where seams will fall, how they will (or won’t) match, etc. Lots and lots of pre-planning will help you end up with a countertop that you love,