We now come to the subject of stains. I will give a number of receipts for stains, but cannot vouch that the colors given will always be obtained, so much is dependent upon the materials employed, the skill in compounding and the heat to which they are fired, but still more is dependent upon the glaze over them, if they are used as stains for slips or the glaze with which they are mixed, if used as glaze stains. For instance, crimson, If mixed with a clay slip, will yield almost no color at all; if mixed with a slip containing little clay, a large quantity of paris white and some glaze, will, when coated with the proper glaze, yield a fine crimson color. If the glaze contains much borax the resulting color will be purple or lilac. If the glaze contains little or no lime the result will be a reddish brown. So if mixed with glaze. In a lead glaze, short in lime, the result will be reddish brown; in a glaze with much lime the result will be crimson; in a glaze with much borax the result will be purple or lilac. By proper compounding, then, crimson stain can be made to yield almost any color from brown, through red brown, to crimson; through the crimson into purple, and then to lilac, and pink can also be obtained from it Lime will ruin orange. I want to say right here that with chromium, iron and cobalt, properly used, nearly any color can be made; that is, with one or all of these used as stains, and used in the proper way. Certain tones are not attainable, but the crude color is. From cobalt we get our blues, in any shade, by proper combinations. From chromium alone we get greens of all shades, reds, crimsons, pinks, lilacs, browns. From iron alone, reds, oranges, yellows, browns. Cobalt and chromium, properly used, give us the different shades of blue-greens and purples; chromium and iron, the rich shades of brown; cobalt and Iron, grays and blacks; chromium, iron and cobalt, rich blacks and sombre greens. For some tones we resort to the other metals. Copper for greens, uranium for amber, yellow and some browns; iridium for the finest blacks, platinum for grays that will come uniform In color, gold for rose and certain purples, manganese for certain browns, antimony in low heat work for certain light yellows, titanium for certain pinks, nickel for peculiar greenish-gray effects, but particularly as a modifier of the other metals. Certain peculiar and fine effects are obtained by the use of chromates, using them as direct stains. Chromate of iron (native) gives different shades of brown; chromate of iron (precipitated) gives a much redder brown; chromate of cobalt gives from light greens to dark blues with a greenish effect; chromate of copper gives some very peculiar greens, some of them very fine; chromate of manganese, from light greenish brown or brownish green to a very deep, rich green brown or bronze green; chromate of nickel gives some very pretty greenish grays. The chromates of potassium, magneslum, barium, zinc, lead and lime can be made to yield either greens, reds, pinks or purples, depending upon the treatment given them, remembering that lime, in combination with tin, brings out the red effects, and that borax or boracic acid alters this into purplish tints. Without lime or tin the tendency is to greens.

I will only give some of the high heat stains. There is no use of going into the soft overglaze colors, as very few of them will stand beyond a cherry red heat. Chrome greens, cobalt blues, iron yellows, browns from chrome and iron, nickel greenish grays, uranium yellows, platinum grays and iridium blacks, and their combinations, will usually stand well up to very high heats. The tone of the color varies as the heat changes, but they can be relied on to give quite certain effects. Gold and antimony colors stand little heat Copper stands to about the point where Albany slip clay begins to fuse. It then loses the beautiful green tint and begins to get brown. Manganese stands to a good heat, but changes color quickly; so does iron, when used in large quantities, especially when used in or under a strong lime glaze.

Pinks.

 

No. 1. Fire Hard -

 

Oxide of Tin........................

60

Paris White.........................

32

Bichromate Potash .......................................................

8

 

100

By hard fire is meant to the heat where Albany slip clay becomes a rich brownish black glaze, even to the point of running and turning gray.

Medium Fire. - Till Albany slip clay becomes a smooth brown or black-brown glaze.

Medium Easy. - Till Albany slip clay becomes a brown semi-glaze, or between a semi-glaze and a glaze.

Easy Fire. - Till Albany slip clay, 90 parts, red lead, 10 parts, becomes a semi-glaze.

No. 2. Fire Hard -

 

Oxide of Tin......................

47

Paris White.......................

23.5

Flint .................................................

23.5

Bichromate Potash ...........................

6

 

100.0

No. 3. Substitute chromate of lead for bichromate potash in

No. 1. No. 4. Substitute chromate of lead for bichromate potash in

No. 2. No. 5. Substitute chromate of barium for bichromate potash in No. 1. No. 6. Substitute chromate of barium for bichromate potash in No. 2.

Others can be made by substituting chromic acid or green oxide of chromium for the bichromate potash in Nos. 1 and 2. Slightly different results will be obtained from each. I prefer the insoluble chromate of lead or chromate of barium.

No. 7. Hard Fire—

 

Oxide of Tin ..............................................

64

Paris White ...............................................

32

Chromate of Lead ...................................

4

 

100

Lilac. Medium Easy to Medium Fire -

Oxide of Tin.....................

4.17

Borax ...........................

41.67

Flint ............................

29.16

Feldspar .........................

8.33

No. 7 Pink.......................

16.67

   
 

100.00

This will stain a lead glaze lilac by using about one of lilac to two of glaze, or, by mixing with clay, will make a lilac slip. Can be made stronger by using more of Pink No. 7 or by using more of the chromate of lead in making Pink No. 7.

Common oxide of manganese is contaminated with iron and does not yield a good brown. Pure oxide of manganese is expensive. Permanganate of potash yields quite a pure manganese, but must first be fritted. Below is a good way of fritting for a good red-brown stain. The stain will be gray, but it will make a red brown glaze:

Brown Frit. Medium Fire -

 

Feldspar ..................

66.67

Permanganate of Potash .................

33.33

 

100.00

From 3 to 20 per cent in glaze will produce from violet to red brown.

Crimson. Medium Easy Fire-

 

Pink No. 6, after burning and grinding fine ...............

42.83

Paris White......................

9.53

Flint ............................

9.53

White Lead.......................

9.53

Oxide of Tin.....................

14.29

 

14.29

 

100.00

33 1-3 per cent crimson, 33 1-3 per cent lead glaze, 16 2-3 per cent parts white and 16 2-3 per cent No. 4 ball clay will make a crimson slip.