This section is from the book "Spons' Mechanics' Own Book: A Manual For Handicraftsmen And Amateurs", by Edward Spon. Also available from Amazon: Spons' Mechanics' Own Book.
There are several kinds of gold leaf and substitutes for the genuine article. The chief real sorts are "deep" or reddish gold, and "pale " gold, the latter being alloyed with silver. The best of these comes from Italy. Silver leaf is often employed for economy sake, and afterwards coloured or varnished yellow. Dutch leaf is a base metal alloy exhibiting almost the characteristic appearance of gold. The various kinds of leaf are sold in " books ": gold books contain 24 leaves 3 in. square and cost 1s. 6d.; Dutch books have the same dimensions, and cost about id.; silver books contain 48 leaves 4 1/2 in. square, and cost about 9d.
The composition of size for attaching gold leaf varies not a little. One of the most common kinds is that called "oil gold size." It is made by boiling litharge in linseed-oil (1 oz. of litharge in 1 pint of oil). Its only disadvantage is that it takes about 12 hours to dry sufficiently to receive the leaf; but it possesses the important advantage of resisting the effects of the weather. even when not varnished. It is of ten sold in admixture with ochre (either yellow or red), ready for application. A substitute generally employed on indoor work is "japanners' gold size "; this dries in 2 or 3 hours, but is not nearly so durable, and necessitates the application of a coat of varnish to the gold, which is not improved thereby. For bright gilding on glass, Brunswick black, copal varnish, or japanners' gold size containing chrome yellow is often resorted to; but the best medium is a "water size," made of isinglass dissolved in boiling water, with an equal volume of spirits of wine added, and the whole strained through silk.
These are not numerous. One of the most essential is the gilders' brush, or "tip," Fig. 734, which is a broad thin brush, made by glueing camel-hair between 2 pieces of thin card. Next comes a cushion or pad on which to cut the leaves to the required size. This pad, Fig. 735, is a strip of flat wood, of convenient size for receiving the loaves (say 6 to 8 in. sq.), covered with 2 or 3 thicknesses of tightly stretched flannel or baize overlaid by chamois leather, provided with a loop beneath for the thumb, and partially surrounded by a wall of parchment to ward off draughts. Some 2 or 3 paint brushes of various dimensions are useful for fastening the leaf and laying on the size. A very sharp and smooth edged knife is necessary for cuttiug up the leaves as they lie on the pad. A "bob" (Fig. 736) of soft chamois leather stuffed with cotton wool, for pressing the leaves down in place, completes the equipment.