"Richard J Kinch" wrote in message
. ..
The key is the degree of firing to *porcelain* status, which means a
hot and long firing that fully fuses the clay, not like cheap tile
that is just fired enough for partial, porous fusing. Kind of like
casting molten metal versus sintering a powder.

Yep, porcelain is very close to glass. Glass also likes to crack, though.

I would be inclined to think porous materials have better shock resistance,
for the reason that the pores give more flexibility.

Face it, splashing three thousand degree metal on *anything* is going to
crack it in no time. Even made mincemeat of a shock-resistant mullite tile
I made myself.

Tim

--
"California is the breakfast state: fruits, nuts and flakes."
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