Pottery, for Artists, Craftsmen & Teachers

by George James Cox

A glaze with a borax base, if ground dry and mixed with water and re-ground before sieving, will give little trouble if used immediately. It will answer for all grade work and may be used for spraying, dipping, pouring, or painting, with absolute safety.

The ground pitchers and grog may be obtained by pounding up broken biscuit and pieces of fire tile, respectively. This, and the glaze grinding, is, of course, laborious work, and suggests correlation with the Physical Education Department. The drip pan and the round tins make excellent moulds for casting drying bats and working bats.

For casting purposes plates and shallow bowls may be moulded in one piece as described, p. [26]. If no lathe be handy, glazed vases may be used as substitutes, the “waste” being added in plasticine to the neck and base.

For tile-making, strips nailed on a stout board will serve in place of tile boxes. The clay is rolled out on cheesecloth with a rolling pin. Various other expedients for drying cupboards, damp-box, etc., will suggest themselves as the course develops.

The above equipment need not be very costly. With it the students should be capable of producing all kinds of tiles, built, pressed, and cast shapes, decorated in relief, with inlays or in colours or glaze.

SIMPLE RAW GLAZES. COLOURLESS

No.	Materials	Parts	Sieve No.	Cone	Method of Using
I Glossy	Lead oxide, red	50	100. Mesh	.03	Applied evenly with a brush to the green shapes. Fired very slowly. Earthenware body.
	China stone	30
	Flint	10
II Glossy	Borax	70	80. Mesh	2	Green shapes dipped thick and slowly fired. Stoneware body.
	China clay	10
	Felspar	75
	Flint	20
	Whiting	25
III Glossy	Borax	360	100. Mesh	.03	Ground dry for 1⁄2 hour. Wet for 11⁄2. Used when fresh on biscuit (earthenware body) for under-glaze painting.
	Silver sand	160
	China clay	120
	Whiting	20
	Flint	10
IV Glossy	Lead carbonate	130	80. Mesh	.04	Used with metallic oxides for simple colours on earthenware body; both green and biscuit.
	Calcined kaolin	150
	Flint	50
	Felspar	50
	Whiting	10
	Zinc oxide	10
V Matt	Lead carbonate	375	120. Mesh	.04	Used thick on hard white earthenware (CC) body.
	Kaolin	210
	Felspar	175
	Flint	120
	Whiting	105
	Zinc	25
VI Matt	Lead carbonate	120	100. Mesh	.02	Used thick on stoneware body. Coloured with 3 to 7 per cent of glaze stains or U. G. colours. The proportion of lead and whiting may be varied as found expedient.
	China clay	50
	Felspar	80
	Flint	15
	Whiting	45
VII Enamel	Borax	70	80. Mesh	.07-.05	Used with various combinations of cobalt oxide, copper oxide, and iron oxide and copper carbonate, giving wide range of blues and greens. On stoneware body.
	Lead carbonate	300
	China clay	50
	Felspar	120
	Lynn sand	50
	Tin	40

All the above colourless glaze masses may be coloured with combinations of the various metallic oxides, or from 3 to 7 or even 10 per cent of glaze stains or under-glaze colours.

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