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doing glaze calculation

updated sun 21 jan 07


Tom Buck on sat 20 jan 07

1970's!! wow you bring back memories -- I too did glzcalc by
longhand back then. Using the "Watts" formula (see Parmalee/Harmon) as
model I designed a set of glazes for Cone 3 Oxidation.

It is a little odd to me to read your list of "atoms" whereas in
fact when we do glzcalc we are talking in units of molecular weights,
called "moles" by chemists.

And you should know too that the world's chemists have also
decided to renumber the Period Table of The Elements... it now goes from
Group 1 to Group 18, with no "A's" and "B's" -- makes for fewer errors.

When we make glass out of powders in a water-based slurry, we
essentially use some Oxides of Groups 1 & 2 metals as "melters", and some
Oxides of Groups 13 & 14 elements as "modifiers" and glass-formers. A
number of Oxides of some elements in Groups 4 to 12 will act as
"colourants" and surface modifiers. There are also a few other elements
that will make unusual glasses, but these are mostly beyond the needs of
potters (eg, fluorine glasses used for scintillators, ie, detectors of
sub-atomic particles).

You can find data on The Elements at


If you wish to read a bit about using glzcalc, go to the
website and track down my article on Raku Lustres -- I wrote this a decade
ago hoping to wean rakuers off the 80-20 base glaze mix.

If you wish a background writeup on "The Mole" please e-mail directly.

bye for now. peace Tom B.

Tom Buck ) -- primary address.
"alias" or secondary address.
tel: 905-389-2339 (westend Lake Ontario, province of Ontario, Canada).
mailing address: 373 East 43rd Street, Hamilton ON L8T 3E1 Canada