Tomato Red Glaze

cone 10 oxidation

Here is a tomato red glaze given as a percentage analysis of the oxides by Brian Sutherland in his book "Glazes From Natural Materials".

Firing profile

Up Fire profile

150 deg F an hour to 250 deg F

400 deg F an hour to 2050 deg F

120 deg F an hour to 2250 deg F

60 deg F an hour to 2310 deg F with a hold of 20 minutes at 2310 deg F

Down Fire Profile

A half hour hold at 1750 deg F

A three hour hold at 1700 deg F

slow downfire at 25 deg F an hour in the interval 1700 deg F to 1650 deg F

A one hour hold at 1650 deg F

Clay body is a grolleg porcelain from Tacoma Clay Art Center.

glaze composition

Emperical Formula tomatoRed_0:

K2O        0.14
Na2O        0.08
Li2O        0
CaO        0.56
MgO        0.22

Al2O3        .32
Fe2O3        .24

SiO2        2.9
P2O5        .11

molecular percent Silica 64 %

The bowl is ~3.5 inches in diameter.

inside

outside