ghost leaf on saturated iron glaze

The glaze satIron_ZG_Z3N_EPK is the second glaze in this note .

Here, satIron_ZG_Z3N_EPK has been applied substantially thicker, but the leaf wash was not applied
correspondingly heavier. The result, as seen below, is a ghost leaf.

With a thick glaze application, the leopard spots seen previously are nearly invisible, yet a dusting of coppery
colored metallic crystals has replaced them. It is a different yet equally interesting glaze.



Image of the plate with glaze satIron_ZG_Z3N_EPK and leaf wash leaf_Z3K.

full view

inside

full view

outside

plate is ~ 7 inches in diameter.



oxidation firing to cone 10 in an electric kiln

Firing profiles

Up Fire profile

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

Down Fire Profile

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

Clay body is a grolleg porcelain from Clay Art Center in Tacoma, WA.



glaze composition

Empirical Formula satIron_ZG_Z3N_EPK:

K2O        0.13
Na2O       0.57
CaO        0.28
MgO        0.02

Al2O3      0.73
Fe2O3      0.24

SiO2       3.65
P2O5       0.07

molecular percent Silica 64%



Empirical Formulae of leaf wash glaze leaf_Z3K:

K2O        0.43
Na2O       0.53
CaO        0.04

Al2O3      0.54

SiO2       3.33
P2O5       0.15

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
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.



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