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iron reds for ^6 ox

updated sat 7 jul 07


John Sankey on sat 30 jun 07

I've been looking around ClayArt and there seem to be two totally
different versions of "Randy's Red", and a few others:

Randy's Red
Gertsley borate-30%

Randy's Red
Gerstley borate-50%

Touchtone Red
Gerstley borate 31
flint 30
feldspar 20
talc 14
RIO 15

46 Gerstley borate
22.5 EPK
29.5 silica
2 soda ash
11% RIO

And, at
there is a glaze labelled as G2826 that looks gorgeous red
streaked with yellow but with no recipe.

Which of these might be most reliable to get deep intense reds?
Does anyone have the recipe used for G2826?

John Sankey on tue 3 jul 07

Ron raises an interesting point: many authors state that iron
reds depend on low alumina and go brown with high, but two of the
recipes I quoted have alumina well below limits (0.2 range unity)
while the other two are mid-range (0.3). Furthermore there is a
Berry Red in the archives that is a bit high (0.4) ...

Slow cooling is mentioned by most authors, as is the need to put
them on thick.

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John Sankey on fri 6 jul 07

The Many Faces of Iron: An Exploration in Cooling, Ceramics
Monthly, June/July 2007, p.54
is interesting for anyone using iron reds - Carol Marians
identifies the same two temperature regions I found with iron and
a high-calcium glaze (see

I'll give her's a try to see if I can identify the crystals

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