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 is a local reduction celadon, the inlay glaze is a saturated
iron.
Several closeups of the interaction region of the two glazes are shown, and
additionally, a closeup
The background glaze is longquan_n_song_Z2S_1, the inlay design is
glazed with satIron_mashiko_neph_Imerys.
The design is created by adhering a mask and then applying the main
glaze. After drying,
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
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
K2O 0.11
Al2O3 0.44
SiO2 3.79
molecular percent Silica 72%
Added:
Silicon Carbide 0.2%
Cobalt Carbonate 0.025%
K2O 0.08
Al2O3 0.61
SiO2 4.03
molecular percent Silica 66.7%
of the matrix glaze. For context, a picture of the
pot is shown.
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
Image of the piece
bowl with glaze longquan_n_song_Z2S_1 and inlay glaze
satIron_mashiko_neph_Imerys
bowl is 10 inches in diameter
oxidation firing to cone 10 in an electric kiln
Firing profiles
Up Fire profile
Down Fire Profile
Clay body is a grolleg porcelain from Tacoma Clay Art Center.
glaze compositions
Background glaze
Empirical Formula longquan_n_song_Z2S_1 :
Na2O 0.13
Li2O 0.09
CaO 0.48
MgO 0.10
ZnO 0.09
Fe2O3 0.02
Inlay Glaze
Empirical Formula satIron_mashiko_neph_Imerys:
Na2O 0.11
Li2O 0.28
CaO 0.51
MgO 0.02
Fe2O3 0.25
P2O5 0.15