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glaze test for lana's metallic black ^6 ox.

updated thu 28 feb 08


Alisa Clausen on wed 27 feb 08

Glaze test for Lana's Metallic Black, ^6 ox.

Source: Clayart

Credited to: Ron Roy, John Hesselberth, Lana Wilson

Fired on mid fire white stoneware

Firing ramp with an electric controller is:
100c p/h to 600c (212f - 1112f)
150c p/h to 1140c (302f - 2084f)
80c p/h to 1220c (176f - 2228f)
15 min. soak
cool down max. to 900c (1652f)
Hold 30 minutes

Shut off kiln

Colorants or additives to a 100 gram batch are measured in percent to the
100 gram batch.
Standard Substitutions in all tests:
Local Boron Frit is used for Frit 3134
Forshammer (a half and half Potash and Soda spar) is the only Feldspar used
Local Boron Frit is used for Gerstley Borate
All substitutions are done not by Mol. Wts., but gram for gram.

Recipe Name: Lana Metallic Black (MC6G Glossy Base 2)
Cone: 6 Color:
Firing: Surface: Metallic
Amount Ingredient
26 Frit--Ferro 3134
22 Feldspar--Custer
5 Talc
4 Kaolin--EPK
17 Silica
100 Total
5 Iron Oxide--Red
2 Manganese Dioxide
2 Cobalt Oxide
1 Chromium Oxide
1 Titanium Dioxide
Unity Oxide
.25 Na2O
.109 K2O
.172 MgO
.469 CaO
1.000 Total
.24 Al2O3
.397 B2O3
.002 Fe2O3
3.744 SiO2
.001 TiO2
0 P2O5
15.6 Ratio
5.2 Exp

Glossy, black covering glaze. Looks black from a distrance, but has a lot
of white fur when viewed close up. This test has 2% Titanium Diox. to get
the fur in the surface. Use less for a more even black.

Note to Alisa from John Hesselberth regarding food safety:
Feb, 2008
I did test it in November of 2004.
Documented on page 33 of my notebook G2.

Anyhow it tested great:

Cobalt 0.03 mg/l
Manganese <0.02 mg/l
Chromium <0.02 mg/l
I used Licorice as a control and got 0.06 mg/l on it. Those numbers are all
the same. When they get that small you get a fair amount of variability.