Lili Krakowski on thu 21 oct 10
Albany Slip was not a "miracle drug", nor exclusive. It was (and still =3D
is, of course, buried under sub-divisions) a natural dark firing clay, =3D
of which there are many around the world. Its composition was not =3D
consistent, any more than that of other "found" clays, and so each
new batch had to be tested. And published analyses differed.
When Albany Slip "disappeared" I made up two substitutes for it.
Albany Slip Substitute I
RedArt 84.7
Dolomite 11.7
Whiting 3.6
I use this for recipes in which no extra iron is called for.
Albany Slip Substitute II
Red Art 66.7
Kentucky Ball Clay 16.7
Dolomite 8.3
Wollastonite 8.3
I wet mix these substitutes, let them dry, and store, using them as =3D
needed. =3D20
Since I designed these in 1999 (published in PMI Summer 2000) I have =3D
found plain old RedArt does as well. And I would expect other
red clays will do fine, just fine.
I "designed" these because I wanted to replicate the Hobart Cowles =3D
"Twice Fired " glazes published in CM May 1984.
The joy of these was/is that at c.5 or 6 (mine are c.6) these glazes are =
=3D
brown. Refired to cone 04 they turn red, gold, and like that. Several =3D
potters have experimented with these glazes in their digital kilns, with =
=3D
specific cooling cycles and holds. As I do not have
a digital kiln, nor intend to get one, I hope someone else will diddle =3D
with these glazes and squeeze the last
ounce of red or gold out of them!
Of these glazes (named for my great nephews and nieces, though the =3D
"nieces" are not really dark brown) Ari and Noah (real life brothers) =3D
are the closest to what you want.
Ari's Plum Jam
Gerstley Borate 21
Bone Ash 4
(Washed) Wood Ash 4
AS Substitute I 57
Silica 14
Fe2O3 7
This tends to be transparent so cut back on the GB. to adjust to your =3D
needs.
Noah's Sherry=3D20
This became the most popular of these glazes when they were published. =3D
Amusingly the glaze was
renamed "Noah's Port" by some.
Gerstley Borate 25
Bone Ash 7
(Washed) wood ash 7
AS Substitute I 44
Silica 17
Fe2O3 7
As I no longer have GB I would use Frit 3195 and test.
I do not know how densely opaque you want your glaze. Make some tests =3D
cutting back on the GB.
Lili Krakowski
Be of good courage
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