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^6 clear

updated wed 5 nov 97


Don Jung on tue 4 nov 97

Just a note on this glaze (it's similar to a glaze posted before on
Clayart...way back), I've tested it and it has a tendancy to 'shiver'
because of the very low expansion. It comes out clear but also burns
off the color of many stains and oxides. I find the coat also a bit
thin with no depth (edges will show).

Try these:

Patti's Crystal Clear (from Clayart a while back)
Nepheline syenite 30
Gerstley borate 21
Wollastonite 9.285
EPK 10
Flint 26.198

Clear 4321 (from Clayart, but can't remember who)
Soda feldspar 40
Gerstley borate 30
Ball clay 20
Flint 10

They are both still high in boron and will tend to burn out colors, but
seem to work better than the simple clear. Fairly forgiving on thick
spots, but will start to cloud if really thick. Got a raft of others
that need testing. If I encounter that perfect clear...I'll let you

Don Jung
in submerged Vancouver (was nice and dry for the weekend, so can't
>----------------------------Original message---------------------------
Ron Roy wrote:

Just in case - anyone who tries this glaze - there is a good possibility
this glaze will break ware - it has a low expansion and may present fit
problems with many clay bodies. It is also oversupplied with boron which
makes it a "soft" glaze - likely to leach and perhaps discolour. I
recommend you test for both fit and durability before committing to it.

>----------------------------Original message----------------------------
>here is a clear glaze that i got years ago from ceramic monthly. i found it in
>an article by dorothy haffner. it is a ^5 - 7 oxidation. it works very well
>over underglazes. it has never crazed over porcelain, but i have never tried
>it over stoneware.
>Gerstley borate........50 gms
>EPK............................17.5 gms
>i use it very thinly on bisqued ware.