Cellular Network
The glaze satIron_ZG_Z3N_Z3T seen
here developed leopard spots.
I wondered, "what would even more MgO do?", and the glaze shown here,
satIron_ZG_Z3N_Z3U, resulted.
The intent had been to further increase the MgO by replacing some alkali
metals with MgO. This is the major
The surprise: The prominent leopard spots of satIron_ZG_Z3N_Z3T in the matrix
glaze are reduced to decorative
This cellular network is the remains left behind by bubbles popping in the
glaze at a point in the firing late
plate is ~ 7 inches in diameter.
150 deg F an hour to 250 deg F
400 deg F an hour to 1800 deg F
300 deg F an hour to 2050 deg F
120 deg F an hour to 2310 deg F with a hold of 20 minutes at 2310 deg F
300 deg F an hour to 1850 deg F then a 2 hour hold at 1850 deg F
300 deg F an hour to 1750 deg F then a 1 hour hold at 1750 deg F
300 deg F an hour to 1700 deg F then a 3 hour hold at 1700 deg F
25 deg F an hour to 1650 deg F then a one hour hold at 1650 deg F
K2O 0.17
Al2O3 0.73
SiO2 3.45
molecular percent Silica 62.9%
K2O 0.43
Al2O3 0.54
SiO2 3.33
molecular percent Silica 48%
A leaf is softened by soaking in water laced with trisodium phosphate. After
the pot is glazed, the leaf is pressed
difference between these two glazes,
although the alumina, and with it the silica, decreased very slightly.
flecks centered in a hexagonal cellular
pattern, which is prominently seen surrounding the leaf. It is present over
the entire plate, yet as it's primarily a change in the texture of the glaze
surface, its visibility
depends greatly on the lighting.
enough that they are not ironed out
by further chemical reactions within the glaze. In this glaze the result of
the popped bubbles is not leopard spots, but rather this hexagonal cellular
network,
resembling a mud crack pattern.
Image of the plate with glaze satIron_ZG_Z3N_Z3U and leaf wash
leaf_Z3K.
oxidation firing to cone 10 in an electric kiln
Firing profiles
Up Fire profile
Down Fire Profile
Clay body is a grolleg porcelain from Clay Art Center in Tacoma, WA.
glaze compositions
Empirical Formula satIron_ZG_Z3N_Z3U:
Na2O 0.44
CaO 0.28
MgO 0.11
Fe2O3 0.23
P2O5 0.07
Empirical Formulae of leaf wash glaze leaf_Z3K:
Na2O 0.53
CaO 0.04
P2O5 0.15
into the glaze. When the glaze
dries, a swatch of plate including the leaf is coated with wax. When the wax
is dry, the leaf is removed and the indentations in the glaze are coated
with a very thin layer of an
underfired glaze.