Iron Yellow

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 1750 deg F then a half hour 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.

Empirical Formula glaze ru_P_tsabar_PMg :

This glaze has 0.2% silicon carbide added.

K2O        0.15
Na2O        0.07
CaO        0.59
MgO        0.17
ZnO        0.02

Al2O3        0.50
Fe2O3        0.02

SiO2        2.54
P2O5        0.01

molecular percent Silica 62.2%

Remarks

The iron yellow glaze here reverts to its origins as an opaque celadon with only a slight increase in firing temperature.

ru_P_tsabar_PMg is also derived from a celadon glaze. It has increased Alumina with the same silica:alumina ratio,
together with an increase in alkali metals.

The matte texture of the glaze ru_P_tsabar_PMg is more stable than the prior iron yellow glaze longquan_n_song_Z2H_0,
so I expect the color also to be more stable.