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^6 oil spot with ^10 3d black base glaze

updated mon 21 feb 11


Robin Wolf on fri 18 feb 11

I have been experimenting with Oil Spot Glazes, using Alisa Clausen's base
& cover glazes as my starting point. I fire ^6 oxi (gas kiln), and ^6
electric. The photos below are a test out of my electric kiln. In testing
the oil spot glazes, I bisque to ^04, and tried some high iron glaze I had
on hand, ^10 3-D Black. I base glazed with the 3-D Black by dipping 1
time for about 7 seconds. Then dipping for a single time (while base glaze
is still damp) for 5 seconds in Alisa's cover glaze #2 with 4% Cobalt.
This combination has had the occasional blister develop where it is
thickest, like at the bottom of a run, but I think that down-firing will
help. I have been firing tests in a 1970's Cress C-20H, (amazing small
kiln) with all peep holes open the entire firing to ^6 tip touching, 1210
degrees C, holding for 15 minutes, then closing it tight and turning the
kiln off. Next step is to try down firing to grow the spots, and avoid the

Photos and glaze recipes available on my new page on my website at


Robin Wolf Pottery

Kingfisher, OK

"Observe the wonders as they occur around you. Don't claim them. Feel the
artistry moving through and be silent." - Rumi

John Britt on sun 20 feb 11

Soak at peak temp for a while to heal the craters or refire or slow the f=
from 6 - 7. Try these:

****Cone 6 Oil Spots
Candace Black cone 6
65g. =3D96 NC-4 feldspar (soda feldspar)
20 g. =3D96 Silica
5g.- Whiting
5g. =3D96 EPK
5g. =3D96 Dolomite
5g. =3D96 Frit 3110

8.0 % Red Iron Oxide
2.0% Cobalt Carbonate

Oil Spot Combo #1 Cone 6
47.83 g.- G-200
23.91g. - Silica
17.39 g. =3D96 Whiting
10.87 g. =3D96 EPK
9.78 g =3D96 Red Iron Oxide

Oil Spot Combo #2 Cover Glaze (apply over #1) Cone 6
30g. =3D96Custer Feldspar
30g. =3D96 Gerstley Borate
25g.- Silica
5g. =3D96 EPK
10g. Zircopax. (Mason stains can be substituted for yellow, blue, etc.)