> Everyone always specifies "unglazed" tiles for baking purpose. Those are
> hard to find unless you strike a well-stocked place. So after asking a
> couple of tile people about it in the badly-stocked local places, I fell
> back on big ordinary-tile glazed ones from the odds and ends box. Only a
> quarter apiece, but you have to get the glue off the back yourself. I have
> been assured -- by store people who don't necessarily know what they're
> doing -- that there is nothing in the glaze to harm anybody.
>
> Has anyone any authoritative information about why "unglazed" is such a
> fabulous key word?
Actually, the primary reason behind this is moisture absorption. A glazed
tile is impervious to moisture. Instead of absorbing the water exuded by
the dough, it'd remain in the dough in the same way as if a metal pan
were used.
An unglazed tile will absorb the moisture into the tile which gives a
much better bottom crust to pizza, breads and similar items. The
most important key when using tiles is to allow adequate time for
the tiles to fully pre-heat.