Hard Glaze.—
| Feldspar | 18 parts |
| Cornwall stone | 3 1/2 parts |
| Whiting | 1 1/2 parts |
| Oxide of zinc | 1 1/2 parts |
| Plaster of Paris | 3/4 part |
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Soft Glaze.—
| White lead | 13 parts |
| Feldspar | 20 parts |
| Oxide of zinc | 3 parts |
| Plaster of Paris | 1 part |
| Flint glass | 13 parts |
| Cornwall stone | 3 1/2 parts |
| Paris white | 1 1/4 parts |
Where clay is used that will stand a very high fire, the white lead and glass may be left out. A wire brush should now be used to remove all superfluous glaze, etc., from the sides and ends of the brick, which is then ready for the kiln. In placing, set the bricks face to face, about an inch space being left between the two glazed faces. All the mixtures, after being mixed with water to the consistency of cream, must be passed 2 or 3 times through a very fine lawn. The kiln must not be opened till perfectly cold.
Process For Colored Glazes.
Preparation Of Colors.
Turquoise.— | |
|---|---|
| Oxide of zinc | 8 parts |
| Oxide of cobalt | 1 1/4 parts |
Grass Green.— | |
| Oxide of chrome | 6 parts |
| Flint | 1 part |
| Oxide of copper | 1/2 part |
Royal Blue.— | |
| Pure alumina | 20 parts |
| Oxide of zinc | 8 parts |
| Oxide of cobalt | 4 parts |
Mazarine Blue.— | |
| Oxide of cobalt | 10 parts |
| Paris white | 9 parts |
| Sulphate barytes | 1 part |
Red Brown.— | |
| Oxide of zinc | 40 parts |
| Crocus of martis | 6 parts |
| Oxide of chrome | 6 parts |
| Red lead | 5 parts |
| Boracic acid | 5 parts |
| Red oxide of iron | 1 part |
Orange.— | |
| Pure alumina | 5 parts |
| Oxide of zinc | 2 parts |
| Bichromate of potash | 1 part |
| Iron scale | 1/2 part |
Claret Brown.— | |
| Bichromate of potash | 2 parts |
| Flint | 2 parts |
| Oxide of zinc | 1 part |
| Iron scale | 1 part |
Blue Green.— | |
| Oxide of chrome | 6 parts |
| Flint | 2 parts |
| Oxide of cobalt | 3/4 part |
Sky Blue.— | |
| Flint | 9 parts |
| Oxide of zinc | 13 parts |
| Cobalt | 2 1/2 parts |
| Phosphate soda | 1 part |
Chrome Green.— | |
| Oxide of chrome | 3 parts |
| Oxide of copper | 1 part |
| Carbonate of cobalt | 1 part |
| Oxide of cobalt | 2 parts |
Olive.— | |
| Oxide of chrome | 3 parts |
| Oxide of zinc | 2 parts |
| Flint | 5 parts |
| Oxide of cobalt | 1 part |
Blood Red.— | |
| Oxide of zinc | 30 parts |
| Crocus martis | 7 parts |
| Oxide of chrome | 7 parts |
| Litharge | 5 parts |
| Borax | 5 parts |
| Red oxide of iron | 2 parts |
Black.— | |
| Chromate of iron | 24 parts |
| Oxide of nickel | 2 parts |
| Oxide of tin | 2 parts |
| Oxide of cobalt | 5 parts |
Imperial Blue.— | |
| Oxide of cobalt | 10 parts |
| Black color | 1 1/2 parts |
| Paris white | 7 1/2 parts |
| Flint | 2 1/2 parts |
| Carbonate of soda | 1 part |
Mahogany.— | |
| Chromate of iron | 30 parts |
| Oxide of manganese | 20 parts |
| Oxide of zinc | 12 parts |
| Oxide of tin | 4 parts |
| Crocus martis | 2 parts |
Gordon Green.— | |
| Oxide of chrome | 12 parts |
| Paris white | 8 parts |
| Bichromate of potash | 4 1/2 parts |
| Oxide of cobalt | 3/4 part |
Violet.— | |
| Oxide of cobalt | 2 1/2 parts |
| Oxide of manganese | 4 parts |
| Oxide of zinc | 8 parts |
| Cornwall stone | 8 parts |
Lavender.— | |
| Calcined oxide of zinc | 5 parts |
| Carbonate of cobalt | 3/4 part |
| Oxide of nickel | 1/4 part |
| Paris white | 1 part |
Brown.— | |
| Manganese | 4 parts |
| Oxide of chrome | 2 parts |
| Oxide of zinc | 4 parts |
| Sulphate barytes | 2 parts |
Dove.— | |
| Oxide of nickel | 7 parts |
| Oxide of cobalt | 2 parts |
| Oxide of chrome | 1 part |
| Oxide of flint | 18 parts |
| Paris white | 3 parts |
Yellow Green.— | |
| Flint | 6 parts |
| Paris white | 4 parts |
| Bichromate of potash | 4 1/2 parts |
| Red lead | 2 parts |
| Fluorspar | 2 parts |
| Plaster of Paris | 1 1/2 parts |
| Oxide of copper | 1/2 part |
Bodies Requiring No Stain: | |
Ivory.— | |
| Cane marl | 16 parts |
| Ball clay | 12 parts |
| Feldspar | 8 parts |
| China clay | 6 parts |
| Flint | 4 parts |
Cream.— | |
| Ball clay | 22 parts |
| China clay | 5 1/2 parts |
| Flint | 5 parts |
| Feldspar | 3 1/2 parts |
| Cane marl | 12 parts |
Black.— | |
| Ball clay | 120 parts |
| Ground ocher | 120 parts |
| Ground manganese | 35 parts |
Buff.— | |
| Ball clay | 12 parts |
| China clay | 10 parts |
| Feldspar | 8 parts |
| Bull fire clay | 16 parts |
| Yellow ocher | 3 parts |
Drab.— | |
| Cane marl | 30 parts |
| Ball clay | 10 parts |
| Stone | 7 parts |
| Feldspar | 4 parts |
Brown.— | |
| Red marl | 50 parts |
| China clay | 7 parts |
| Ground manganese | 6 parts |
| Feldspar | 3 parts |
| In making mazarine blue glazed bricks use the white body and stain the glaze only. | |
| Mazarine blue | 1 part |
| Glaze | 7 parts |
For royal blue use 1 part stain to 6 parts white body, and glaze unstained.