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cone 6 chit chat (good clear semi mat)

updated fri 31 may 96


Michelle H. Lowe on mon 20 may 96

Richard Burkett kindly revised a glaze I have, trying to correct for crazing.

The original is Pale Rutile Blue, posted here previously, way back when.
Over white clay it is a translucent pale blue, reminiscent of celadon. I
fire it at cone 7 oxidation. Over red clay it appears almost transparent.

Pale Rutile Blue cone 6 ox

Gerstley Borate 8.45
Mag Carb 1.86
Whiting 15.30
Wood Ash 14.54
Neph Sy 15.55
Kaolin 10.91
Flint 33.39

Total 100.00

Rutile 1.69

Richard's revision is this (my test results below):

>here's a revision that I just did. Give it a try if you want. I eliminated
>the wood ash to make it more dependable as far as crazing goes. like the
>note says, it may not work, but the original was a bit low in silica and
>alumina so that's mostly what I added.
>Glaze name: Pale Rutile Blue2
>Cone: 6
>Recipe: Amount
>Gerstley Borate 6.55
>Neph Sy 18.10
>EPK 12.12
>Magnesium Carbonate 2.24
>Whiting 22.45
>Flint 38.53
>Total: 99.99
>Also add:
>Rutile 1.69
>Molecular Formula:
> 0.132 KNa0 0.262 Al2O3 2.800 SiO2
> 0.760 CaO 0.082 B2O3 0.002 TiO2
> 0.100 MgO 0.001 Fe2O3
>This version should have less crazing, but may go opaque.
>If that happens, try adding a little (1-2%) lithium carbonate
>to flux it out.

In fact tested over red clay and white clay to cone 7, this glaze appeared
transparent and semi matt, and NOT crazed. But no sign of the pale blue to
be found. GREAT semi mat clear, left underglazes true to color really

Michelle Lowe, potter in the Phoenix desert \|/ | -O- | | /|\ | | |
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