Art Bronzes

These are bronzes of different tints, showing a great variety according to the taste and fancy of the operator.

I

After imparting to an object a coating of vert antique, it is brushed to remove the verdigris, and another coat is applied with the following mixture: Vinegar, 1,000 parts, by weight; powdered bloodstone, 125 parts, by weight; plumbago, 25 parts, by weight. Finish with a waxed brush and a coat of white varnish.

II

Cover the object with a mixture of vinegar, 1,000 parts, by weight; powdered bloodstone, 125 parts, by weight; plumbago, 25 parts, by weight; sal ammoniac, 32 parts, by weight; ammonia, 32 parts, by weight; sea salt, 32 parts, by weight. Finish as above.

Antique Bronzes

In order to give new bronze castings the appearance and patina of old bronze, various compositions are employed, of which the following are the principal ones:

I

Vert Antique: Vinegar, 1,000 parts, by weight; copper sulphate, 16 parts, by weight; sea salt, 32 parts, by weight; sal ammoniac, 32 parts, by weight; mountain green (Sanders green), 70 parts, by weight; chrome yellow, 30 parts, by weight; ammonia, 32 parts, by weight.

II

Vert Antique: Vinegar, 1,000 parts, by weight; copper sulphate, 16 parts, by weight; sea salt, 32 parts, by weight; sal ammoniac, 32 parts, by weight; mountain green, 70 parts, by weight; ammonia, 32 parts, by weight.

III

Dark Vert Antique: To obtain darker vert antique, add a little plumbago to the preceding mixtures.

IV

Vinegar, 1,000 parts, by weight; sal ammoniac, 8 parts, by weight; potassium bioxalate, 1 part, by weight.

Brass Bronzing

I

Immerse the articles, freed from dirt and grease, into a cold solution of 10 parts of potassium permanganate, 50 parts of iron sulphate, 5 parts of hydrochloric acid, in 1,000 parts of water. Let remain 30 seconds; then withdraw, rinse off, and dry in fine, soft sawdust. If the articles have become too dark, or if a reddish-brown color be desired, immerse for about 1 minute into a warm (60° C. or 140° F.) solution of chromic acid, 10 parts; hydrochloric acid, 10 parts; potassium permanganate, 10 parts; iron sulphate, 50 parts; water, 1,000 parts. Treat as before. If the latter solution alone be used the product will be a brighter dark yellow or reddish-brown color. By heating in a drying oven the tone of the colors is improved.

II

Rouge, with a little chloride of platinum and water, will form a chocolate brown of considerable depth of tone and is exceedingly applicable to brass surfaces which are to resemble a copper bronze.

Copper Bronzing

I

After cleaning the pieces, a mixture made as follows is passed over them with a brush: Castor oil, 20 parts; alcohol, 80 parts; soft soap, 40 parts; water, 40 parts. The day after application, the piece has become bronzed; and if the time is prolonged, the tint will change. Thus, an affinity of shades agreeable to the eye can be procured. The piece is dried in hot sawdust, and colorless varnish with large addition of alcohol is passed over it. This formula for bronzing galvanic apparatus imparts any shade desired, from Barbodienne bronze to antique green, provided the liquid remains for some time in contact with the copper.

II

Acetate of copper, 6 parts; sal ammoniac, 7 parts; acetic acid, 1 part; distilled water, 100 parts. Dissolve all in water in an earthen or porcelain vessel. Place on the fire and heat slightly; next, with a brush give the objects to be bronzed 2 or 3 coats, according to the shade desired. It is necessary that each coat be thoroughly dry before applying another.