Zircon Crystals
The glaze oribe-woof-PAlZr is high in calcium and contains zirconium. It is
dark green with intriguing
I show a close up of the micro-crystals in addition to an image of the bowl.
bowl is ~ 4 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 hr hold at 1850 deg F
300 deg F an hour to 1750 deg F then a 1 hr hold at 1750 deg F
300 deg F an hour to 1700 deg F then a 3 hr hold at 1700 deg F
25 deg F an hour to 1650 deg F then a 1 hour hold at 1650 deg F
K2O 0.10
Al2O3 0.41
SiO2 2.97
molecular percent Silica 66%
Added:
5% copper oxide
snowflake like crystalline inclusions. As well as
being an opacifier, I note that zircon can also create visible
micro-crystals
in a glaze.
Close up of crystals
Image of the glaze oribe-woof-PAlZr
inside
outside
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
Empirical Formula oribe-woof-PAlZr :
Na2O 0.03
CaO 0.71
MgO 0.16
P2O5 0.01
ZrO2 0.11