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fwd: re: cornwall stone/spodumene

updated sun 24 oct 04

 

Gary Navarre on sat 23 oct 04


---------------------------- Original Message ----------------------------
Subject: Re: Cornwall Stone
From: "lela martens"
Date: Fri, October 22, 2004 7:22 pm
To: CLAYART@LSV.CERAMICS.ORG
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Hi Lou,

Here is one recipe. I have only done a small test tile with it so far, and
that came out very nice. I will be testing further in my next firing. I
also don`t know about it`s stability, or even where it came from, an old
recipe hanging around our guild room.
Note the lithium.

Tenmoku Gold cone 5 - 6

cornwall stone----------61.0
whiting-------------------8.0
gerstley borate--------3.0
lithium carb-------------5.5
dolomite-----------------7.0
flint------------------------5.5
add red iron oxide----10.0

Lela


Hay Lela and Crew,
When Dart clayed this stuff foreword to me he put in some Spodumene and
said "Here's all the lithium you'll probably ever need". Ya think that
would be a good enough source for the lithium for the above formula
should I find myself needing a lower temperature glaze? I think there's
some dolomite too, although I can find hundreds of pounds of pieces
scattered about in the area. The whiting, gerstley borate, flint, and
iron I also have somewhere. Looks like I might have the ingredients for
that base glaze + any oxide.
I'm also wondering if I were to eliminate the gerstley borate would that
tend to raise the melting point?
Thanks and keep going!

G. in Da U.P.
Navarre Pottery
Norway, Michigan, USA