It does look like quartzite but for sure I would test it. It's also a smart idea to test the porosity.

I don't see any cross bedding on that slab. There's a hint of a layered look maybe those were once sedimentary layers, but I can't say for sure.

The broken corner looks to be coated with epoxy. No worries there.

Thank you! Especially on the corner, I wasn't sure what was going on there. I agree about no significant cross-bedding, but I wasn't 100% sure on some parts of the layering. But I'm glad you don't see any, that makes me feel better!

I'm trying to get a sample of it, I have to go back next week so hoping they can give me one then. They haven't said for sure that I can get one, which is frustrating.

did they give you a name?

a sure way to test for quartzite as opposed to marble is the glass scratch test. you could probably even do it on the broken corner of the slab.

you could get a glass tile (like a subway tile, or a spare piece of glass if you have it) and run it across the broken portion of the slab.

Marble is softer than glass. So, if that slab turns to powder on top of the glass, you have marble. If that stone/slab edge actually scratches the glass (to where you see and feel a distinct ridge or cut in the glass) then you have a quartzite (or granite)

the other way to tell is lemon juice. Quartzite will not etch. ever. Marble will. always.

take some fresh lemons with you (or white vinegar) and put some drops on the slab corner (make sure they give you a sample of the exact slab you're looking to buy, not some other slab sample) Wait about 5-10 mins. wipe off. can you see an etch mark? it's marble.

an etch mark looks like this (in the top corner) it will remove the polished finish and fill a bit rough

this is a test I was shown. this was untreated marble. see the far left blotch? that's an etch.

Ketchup, oil, lemon, vinegar and some other brown stuff.

Some quartzite will stain, so the stain test isn't a for-sure. the glass test and acid-etch test is.

BTW, no such thing as a 'soft quartzite', or partial quartzite. quartzite is made of almost 95% quartz. If it has some marble in it, or some 'crystal parts', then it's marble!

that slab somewhat resembles a Macaubas quartzite. hard to tell from the pic. maybe Infinity or Fantasy?

maybe SeaPearl?

(this is a true quartzite)

No, it just came in and it hasn't been labeled yet. I think it resembles Sea Pearl, but can't be sure.

I plan to do the scratch test when I go back, but not sure how I can do the other tests without a sample. Really hoping they will give me one.

Interesting what you said about the 'crystal parts', I haven't heard that. I do know that it's either quartzite or not, not soft quartzite (what a bunch of BS they try to sell us, right!?) This slab does have a lot of sparkle to it when I shine my phone light on it, I thought this was because it could be a crystalline quartzite. But now I'm second guessing? Up close, it also looks like it has tiny hairline cracks, but I've seen this in other slabs like Taj Mahal that are definitely quartzite, but they also concern me a little.

it could be quartz crystals. hard to say. but based on what I've seen, if it has those pockets of 'crystals', it's usually marble. but ya never know until you do the test.

Thanks Beth, lI’ll push hard for that sample!

Look for label with bar code on side edge of slab. It will have specific info to uniquely identify the slab. Take a photo of it. That is very important documentation. If they are giving you BS now, it won’t get better. Plenty of sources out there. Hope you can find better supplier.

Thanks! They aren’t giving me BS yet but im anticipating it it. I judt meant that suppliers in general aren’t always honest. I’ve been to so many local suppliers, this one has the best selection by far. I’ll let you all know how it goes when I go back. I put down a deposit to hold it, we have 10 days to decide so I should have some answers soon!

Don't test a sample please. Test the actual slab you're contemplating purchasing only. There is plenty of waste, about 25%, when cutting slabs for fabrication, so your test is hardly damaging a useful part of a slab. No test, no sale.

Thank you! I feel this way too, it is a large expense and they should accomodate sampling.