Janet H Walker on thu 30 jan 97
You asked for a purple glaze. Here's one that I've finally gotten
to test and it may be what you are looking for. I got it from a
community studio where my dad hangs out and I have no idea where
they got it from. I think they called it Deep Purple.
Deep Purple, electric cone 6
Gerstley borate 8.4
Nepheline syenite 14
Custer (potash) feldspar 27
Lithium carbonate 3.7
Magnesium carbonate 1.7 (lite, the white fluffy stuff)
Tin oxide 5
Cobalt carbonate 0.6
Chrome oxide 0.17
Some of the numbers may seem a bit funny but I've proofread this!
It was converted first from a batch recipe and then HyperGlaze keeps
all these decimal points. Some of them probably matter when scaling
back up again.
I think it is important to use these exact ingredients and not to
try for substitutions. I tried calculating an equivalent and one
of the glaze gurus on the list also did a recalculation different
from mine. Both of our tries came out a sort of greyed blue that
isn't terribly attractive. When I finally got the original
ingredients and fired the test side by side with the others, this
one came out purple and the others were blue. But so far I've
only done one test with this glaze and don't know whether it is
reproducible under normal firing (this last firing was, um, one
of those learning experiences.)
You'll also find Brian Kemp's purple in the GlazeBase I think.
I never got around to testing that one.
Cambridge MA USA