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.
Before gilding plain wood, its absorbent character must be destroyed by the application of a ground colour, which may be japanners' gold size mixed with yellow ochre previously ground very fine in turpentine, or a compound of boiled linseed-oil and a pigment of good body, such as white-lead. The painted ground, when dry, is rubbed down smooth with fine glasspaper, and any required number of coats added and similarly smoothed, when the sizing and gilding follow in the usual manner.
In the case of polished wood, the coat of polish serves the purpose of a ground colour, and renders the latter needless. Should the gilding be destined to cover only portions of the surface, the precaution must be taken, before applying it, to rub whiting on the parts not to be gilded, so as to prevent the adhesion of the leaf to the otherwise sticky surface. The sizing and gilding are conducted in the ordinary way.
For gilding on cards, the surface must first be rendered non-absorbent by the application of a water size, made from isinglass, gum arabic, or parchment shreds boiled down. The number of coats of size needed will depend on the nature of the card; then oil sizing and gilding follow in due course. An exception to this rule obtains with photographs, in which the albumenizing serves as a substitute.
The surfaces of textile materials require a similar grounding of water size, which may be weak glue for coarse fabrics.
The same rules hold good as for polished wood.
These are unsatisfactory materials for gilding on, as they so soon suffer oxidation and decay. They are best painted first.
The porous surface of stone or plaster must first be rendered waterproof and "satisfied" by coats of either a solution of shellac and gutta-percha in naphtha, or of shellac in methylated spirit, great care being taken that the surface is previously dry, and that the oil size afterwards applied does not extend beyond the " satisfied " portion.
Ivory is not so easy to gild as articles made of wood: wood, being porous, retains a portion of the gold size; yet, on the other hand, bone or ivory may be so gilt that it shall resemble gold. Free the ivory from dirt or grease; when quite dry, give the article a thin coat of gold size laid on evenly with a fine hair brush; lay aside until set, which may be known by feeling whether tacky to the finger. The gold size should be just the least warm; the article may, with advantage, be warmed before applying the gold size; great care must be used to keep the dust from the article until gilt and quite dry. Cut the gold leaf in suitable-sized pieces, and apply with the tip; the gold leaf may then be pressed into shape with a piece of white wool. Should any part appear not gilt, apply a dab of gold size, then a piece of gold leaf. When quite dry, it may be burnished with an ivory paper-knife, or even a glass penholder, always inserting a piece of tissue paper between the burnisher and the article to be gilt.
When finished off, the appearance will be much improved by giving the article a coat of gold lacquer.
This needs 3 or 4 coats of boiled linseed-oil laid on at intervals of 24 hours, followed by a water size containing finely-ground yellow ochre for delicate work, or a coat of japanners' size and yellow ochre for coarser work; the gold size and leaf follow when this is dry.
The bright effect is gained either by having a smooth polished ground, or by burnishing the coat of gold leaf. The adhesive medium employed is water size. There are two important modifications of the process, according as the surface to be gilt is transparent or opaque.