is there a danger in using unglazed quarry tiles because of the crystaline silica in the tile?
I've been using quarry tiles as a baking surface for a decade at least. I bake weekly, breads, pizza, flatbreads, what have you. I've seen no evidence of hazard to me or mine. Is that proof of much? No. But am I about to stop using them? Not until I've heard something believable from a scientist with a good reputation.
I have looked in all the major stores...lowes, HD and even looked in the smaller tile shops and no one carries quarry tiles just sitting on the shelf.
I purchased my quarry tiles many years ago at Home Depot. I've not looked for them there since because, frankly, I just don't break them the was I broke my pizza stones, one by one. Were it me, I'd go to a Home Depot or a tile store, speak to the supervisor of the tile department of HD or the owner of the store and ask that that person talk to a supplier. They'll have numerous catalogs from suppliers to check in and they'll have phone numbers that you yourself could call if they won't do it for you.
Unglazed quarry tiles are recommended by many (including bread books written by pros) as one of the best choices as a baking stone. ;)
If you can't find it, granite chopping board like this works well, too, and probably easier to find. It's useless as a chopping board because it blunts blades but really good as a baking stone. Usually one side is polished (no chemical is used) and the other unpolished. You use the board with the unpolished side up. (If it has rubber pads to prevent slipping, you'd have to remove them before use) When it's not baking breads, it's very useful as a pastry board, too. (Use the polished side up)
If all fails, find a kiln manufacturer in your area and have a cordierite kiln shelf cut to fit your oven. That's what I'm been using now after quarry tiles (they were square so couldn't bake baguettes or long batard) and granite chopping board (now working as a pastry board, mainly used when shaping dough). There's no known health hazard with cordierite, either, except for dropping it on you foot. :p Out of these three, this is the toughest against thermal shock. The price I paid was about the same as the price for granite chopping board.
what do you think of this over at HD. thank you
I live in UK, so never seen any of the products at HD and I can only tell you what I know from my own experience and a bit of research I did when buying my baking stones. But that's alright with you, from the range above, the only one I know of for sure is granite tile. But when I searched under 'quarry tile' with the search tool led me to this page which has 4 'Ceramic Tile Dura Quarry.'
Both of them should be fine, but you'd have to ask them to make sure they are not treated with chemical. But as I said, the reason I stopped using quarry floor tile was because it's square, which most of floor tiles are. If you only bake boules or small loaf, that's fine. But if you want to bake long batard or baguettes, it's not very useful. That's why IF you go for granite, for example, the chopping board like on the link above is much better option, I think.
When I was looking for a baking stone big enough to let me bake two loaves next to each other, I ended up in desperation buying three Vermont Country Grillstones, which are volcanic cut stones,6x16x3/4 inch. Single price is $24.95, 2-pack is $39.95, 3-pack is $54.95. Around Christmas time or Easter they usually have a sale with substantial savings. I know they are pricy but this has been the best thing I have done for my Sourdough Baking.
I agree with lumos as to corderite, it comes up to temp very quickly, and can stand very high temps better than many other stones. While you can get them from some baking suppliers, there are easy to find from pottery supply stores - they are called kiln shelf or shelves, and you get get round, square, rectangle, and various sizes and thicknesses. In the States, I like to use Axner http://www.axner.com/cordierite-kiln-shelves.aspx if you can't find a local supplier.
I bought 2 of these:
$9.60 ea. 15" x 12" I have a typical electric oven with oven racks. I put the stones on the oven rack overlapped in the center a little. Marked the the overlap with a pencil. Took the tile to the local pumbing/tile shop and they did a trim for a couple of bucks. Now I have 2 stones that I can place on the bottom rack that fit snugly together to fill the entire rack. Crank it up to 500F for Pizza or 450F for loaves. They really work great. I store them in the boxes they came in.
After looking for quarry stones and other pizza stones, this was my solution. The vendor was a little slow. A subtle email reminder helped expedite things. Otherwise - no problem.