The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Baking stone... in London, UK?

GG's picture
GG

Baking stone... in London, UK?

Hi,

Has anybody based in London, UK managed to find a supplier of baking stones? I am determined not to settle for the pizza stones, but try and find unglazed quarry tiles. They do exists here, just have not managed to find a supplier. 

Much appreciate any pointers.

Best,

Nicolaj

LONDON

Chuck's picture
Chuck

I am determined not to settle for the pizza stones, but try and find unglazed quarry tiles.

Why?

I've been baking on unglazed quarry tiles for almost two years now. My experience is very definitely they're not better than a "pizza stone".

Even the cost difference and the availability -which used to heavily favor the unglazed quarry tiles- aren't hugely significant any more, as "pizza stones" have become more readily available for a much lower cost while unglazed quarry tiles have retreated from ubiquity to a specialty item.

GG's picture
GG

Trying to avoid 'pizza stones' as they are still relatively expensive (at least in London) and feedback seems to be that they break more easily.

If I could find unglazed quarry tiles at even cheaper prices at a local store, I would have gone for that. But like you say, they have disappeared from the market.

Checked out the kilns mentioned above, and they are cheaper, come in square sizes and can be modified in size at no extra cost. Corcierite also seems to be more resistant to temp differences. Sounds like a good deal to me.

In London, my conclusion so far is that the evolution you describe has not quite happened yet, and the alternatives to 'pizza stones' are still the better opton.

Cheers,

N

Zeb's picture
Zeb

Hi N and Daisy A,

Just a quick update - my kiln shelf is still all in one piece I didn't condition it, no one suggested it, but at the time I got it Bath Potters seemed a little puzzled that I wanted to use it for bread and were a bit wary about saying it was food safe, but maybe more people have gone that route now.

The pizza stone i started with only lasted a few months and in fact died/cracked all the way through when some tomato passata ran off a pizza onto the stone. Anecdotal but that's what happened.

My shelf is about 3/4 inch thick I think.  I had it cut to leave an inch gap all around, but I think maybe I should have made it smaller, it's a tricky call, too big and the air can't circulate (electric oven). This is a poor photo, but it might give you the general idea. best wishes Zeb

My Kiln shelf and steam tray below

Noor13's picture
Noor13

I am in the Uk close to London as well :)

I got my stone from this site

http://www.pizzastone-shop.eu/

It might be a bit pricey, but I love this stone. Breads and Pizza come out wonderfully.

Take care,Noor

Noor13's picture
Noor13

Oh, and they have a special bread stone, not just Pizza stones

dscheidt's picture
dscheidt

Potters are not bakers. 

There's no reason to put garbage, which is what your slip is, on a stone.  There are all sorts of reasons not to, one of the big ones being "Do you want to eat burnt flour?".   Corderite is non-friable, there's no dust from a fired stone, unless you break it.  (There's probably some on it when it's new, but once that's cleaned it's gone.)  There's no need to oil it, season it or do anything but let it get hot and put a loaf on it. 

Bakers are not potters.

Nor is there any reason to flip it over, store it on its side, or do any of that magic.  If it's convient to store it on its edge, fine, you won't hurt it, except you increase your chances of dropping it.

Rember, a *cold* kiln firing gets to 1100 F (about 600C).  A hot one hits 2400 (*1300 C).  A hot oven gets to 600F.   Stress failures are very much a function of the temperature and rate of change.  You're not going to damage a kiln shelf with a home oven.

Mini Oven's picture
Mini Oven

is a lot to do over nothing.   Sorry, pottery and bread are similar but not the same.

Kiln shelves are not affected by kitchen oven temperatures.  The temperatures are too low.  By conditioning a shelf or stone all what is needed for the home baker is just to gradually warm it up for the first time slowly to dry the thing out.

These shelves are ment to take 600°C (1112°F) plus temperatures which is molecularly hard on the atomic bonding of the stone and that is when special care is needed to flip shelves to prevent sagging.  They become more brittle with the number of high temperature firings that they live through.  Coating them with a wash of kaolin and alumina hydrate (slip) is done to prevent the molten glass from glazes, melting clay bodies and melting metals from bonding into the shelf, which would be a real pain to clean for it would requiring chipping & grinding.  It has to be cleaned off or it will melt and bond to other pots when the kiln is reheated.  This has all to do with ceramics.  Grinding or sanding this hard a surface would be better done with a water cooling grinder... no dust.

A mixture of kaolin and alumina hydrate has a very high melting point and therefore used (like you would rice flour) by potters to prevent sticking.  One very big difference: Flour on the stone will burn!  Kiln wash on a kiln shelf will not burn and remains intact but any drips of glaze or molten metals can be removed or flaked off -- the dried wash sticks and bonds to it preventing running and a bigger mess.  Unlike a kitchen oven, a kiln cannot be instantly opened and the pots removed, it will be days before that kiln is opened.  When glaze or the stuck pot is removed from the shelf, part of the coating is removed too.  The spot is touched up and filled with a quick brush or two of slurry and allowed to dry before the shelf is used again.  The reason for layers is again so that the stuck on piece of pottery will come off easily and remove only the last layer of dried wash.  Several layers protects the shelf better than one layer.  This is for pottery.

Now, if you want to apply this theory to your baking stone, I suggest you get a mineral powder that will not burn in your oven and is approved safe for consumption.  The whole idea of coating the stone is not needed in a home oven.  Molten sugars and such will burn up and out on your stone over several bakes.  Parchment paper would be the best protection for those who want a spotless stone.  Flour dust is very harmful, and on a semi-daily basis, more so than sanding a stone one a year.

Warning: What one should not do is use a used pottery shelf that has been used for ceramics.  Invest in a new one.

Mini

Chuck's picture
Chuck

I also find new kiln shelves work quite well for baking  ...provided you do not do any of the things that are recommend for ceramics use. Don't try to coat it with anything. Don't apply any sort of "slip". Don't do any break-in procedures. Don't sand it. Don't try to clean it.

If you do any of the sorts of things typically done for ceramics or that almost any well-intentioned potter or ceramics salesperson will recommend or that are printed right on the directions that come with the shelf, you will both a) risk some serious health and safety issues and b) have a poor baking experience. Those are all "ceramics" instructions, not "bread" instructions.

The solution for bakers is very simple: let everything that potters tell you and everything the directions that come with the shelf say go in one ear and right out the other.

Chuck's picture
Chuck

I've been following with interest the information about sanding down cordierite and the danger of silicosis. The simplest solution for bakers is simply: don't (not "be careful" or "wear a mask" but simply don't).

(While advice about "kiln shelves" or from potters can be reasonably crossed over to the baking world given sufficient thought and care, on balance the danger of carelessly translating [irrelevant] ideas like "sand the stone" seem to outweigh any possible advantages.  ...I'm pretty sure the original "sand the stone" advice came from either a "kiln shelf" or a "pottery" source, not a "baking stone" source.)

Salilah's picture
Salilah

I had a spare granite "worktop protector" so took the rubber feet off it, and used that

Probably not as good as stone, as it won't absorb - but it shows no sign of cracking - they are currently £10 from Tesco

cheers
S