Articles to be blocked in gold must be prepared with some substance to which the gold will adhere. The finisher uses a fluid or dry adhesive according to the material he is working upon. Of liquid sizes, diluted white of egg or, in some cases, dissolved gelatine or blood serum is used almost exclusively. These liquids, which are applied with a sponge or, for fine work, with a brush, are called the "ground" or "sizing." Of dry adhesives, we know only the gilding powder, which consists of resin with now and then an addition of dried white of egg. The other powders used by the finisher are rice flour or potato flour; these are not used as adhesives but to prevent the gold sticking at places where it is not wanted.

Leather and cloth are sized with white of egg; silk and other woven materials are finished without special sizing, and also surfaced papers and cardboard goods, as they are treated with finishers powder a wet preparation being unsuitable.

Size for blocking is thinner than for hand finishing, and when it has to be washed over the whole of a cloth cover it is still further diluted. Glair for brushing over an impression consists of one part white of egg and one part vinegar; to every 1/2-litre 1 g. of powdered borax is added, the whole beaten to a froth and filtered. For coating over, take one part white of egg two parts water, and to every ½ liter add 10 drops of glycerin and 1 g. borax. If a larger quantity of glair is required for coating over, it may be thinned with water or vinegar; but size made with vinegar must not be applied to fancy colored cloths.

Gilding powder may be yellow or white, the latter kind is rougher and is suitable for silk stuffs and also where blocking has to be done over color on cloth. Yellow powder is softer and is apt to clog the finer cut tools; it is more suitable for the preparation of paper de luxe, for blocking surface and chromo papers, and for photo cases.

Gilding powder is sprinkled by means of a box which has a double layer of fine gauze instead of a bottom. By tapping upon the box a fine shower of powder is dusted on to the surface to be gilded.

Glair is made in the workshop; the powder is bought ready prepared to make it would take too much time.
For blocking in alloyed metals, galantine size is used, as it is a powerful adhesive. A tablet of gelatin is soaked in 1/4-litre of water overnight and next morning is dissolved in the bath. Gelatine is used to cover the whole surfaces and is laid on when lukewarm. Blood serum serves the same purpose. Ox blood is allowed to coagulate and the hardened mass thus produced is placed over a cloth strainer, or hair sieve, and the liquid albumen allowed to drain from it; the process is hastened by cutting the caked blood into small pieces. Only the clear liquid which is strained off is to be used a pinch of borax will make it keep longer.

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