Interacting glazes at a vertical interface

Glazes interacting at a vertical interface.

The matrix (i.e. background) glaze and inlay glaze do not overlap before firing.

The matrix glaze contains alkali metals, some iron, and has micro-crystals. The inlay glaze
is a microcrystalline matte containing both barium and strontium.

Several closeups of the interaction region of the two glazes are shown, and additionally for context,
a picture of the pot is shown.

The background glaze is satIron_Alex_Puah_14, the inlay design is glazed with hankPaper_Z1R_2C_1Var.

The design is created by adhering a mask and then applying the main glaze. After drying,
the mask is removed and the open area filled in with a second glaze, using a bulb syringe
with a needle applicator.

Close up Images of the interaction region

full view

Close up Image of the matrix glaze

full view

Image of the piece

full view

mug with glaze satIron_Alex_Puah_14 and inlay glaze hankPaper_Z1R_2C_1Var.

mug is ~4 inches high

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
200 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 1750 deg F then a 50 minute hold at 1750 deg F
300 deg F an hour to 1700 deg F then a three 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 Tacoma Clay Art Center.

glaze compositions

Background glaze

Empirical Formula satIron_Alex_Puah_14 :

K2O        0.07
Na2O       0.33
Li2O       0.14
CaO        0.30
MgO        0.16

Al2O3      0.64
Fe2O3      0.07

SiO2       2.97
P2O5       0.04

molecular percent Silica 62.7%

Inlay Glaze

Empirical Formula hankPaper_Z1R_2C_1Var:

K2O        0.13
Na2O       0.12
Li2O       0.05
CaO        0.14
MgO        0.01
BaO        0.31
SrO        0.24

Al2O3      0.43

SiO2       2.7
TiO2       0.14

molecular percent Silica 63.4%

Added:

Cobalt Carbonate 1%
Copper Carbonate 0.5%

Remarks

Note the acicular crystals growing in the interaction region and clustered in the matrix glaze at the edge
of the interaction region.

This glaze has a slight luster, which is difficult to capture in a photograph, but is faintly visible
in the last close-up.

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