Chrome Pink
cone 10 oxidation
The Downfire profile
A half hour hold at 1750 deg F
A three hour hold at 1700 deg F
slow downfire at 25 deg F an hour in the interval 1700 deg F to 1650 deg F
A one hour hold at 1650 deg F
Clay body is a grolleg porcelain from Tacoma Clay Art Center.
We last saw the glazes paperWhite_ZO_1 and paperWhite_ZO_1 with added alumina in:
We added a bit of alumina hydroxide to the paperWhite_ZO_1
that remained after a previous firing, and saw a bit of pink on the rim.
.
paperWhite_ZK_2 is a properly weighed glaze with a measured addition of
Alumina to its Emperical Formula.
It's emperical formula except
for Alumina is unchanged from that of paperWhite_ZO_1.
It has .2 %
chrome oxide added.
the bases in it's Emperical Formula are half alkali metals and half
alkaline earths.
The alkali metals:
K2O 0.21
Na2O 0.23
Li2O 0.05
The alkaline earths:
CaO 0.2
SrO 0.3
with a trace of MgO.
Al2O3 .6
SiO2 3
The result is a dry matt glaze which is pink fading to white where thinly
applied, and a deap almost red where thick.
There are bits of aqua and green
both where the glaze is thin e.g. at the glaze line on the foot,
but also
where the glaze is exceptionally thick and flowed into the center of the
pot.
The glaze is shown on a 5 inch diameter shallow bowl.
paperWhite_ZK_2 with 0.2 % Chrome oxide
Commentary
The result is sufficiently close in appearance to the original test that likelythis effect is stable over a composition range perhaps between Alumina .55 and .62.
As this glaze is a rather dry matt, subject to pinholing if not carefully applied,
it will be interesting to explore glazes with alumina in the range between that of the two glazes
paperWhite_ZO_1 and paperWhite_ZK_2.