Larry,
I have always thought that the reason behind using UNglazed tiles
in the oven for pizza, bread, etc... was that the unglazed is pourous and
therefore will adsorb moisture from the bottom crust and make it crispy-
vital in pizza-making. Your glazed tiles have that seal that does not allow
this moisture exchange. So baking with the glazed tiles, I would guess,
would
give a final product somewhere between the unglazed-version and the
pan-version. But, hey, since it works for you -stick with it.
As far as lead, etc... It might depend on the kind of glaze (?) I know that
clay
bakers (used not only for breads, but casseroles, roast chickens, etc...)
are glazed and need to be greased like a regular pan. But the question is:
do tile manufacturers use the same glaze/process as manufacturers who
make bakeware?
I would call the manufacturer, if I were you, just to be on the safe side!
Good luck,
Pam D