This section is from the "Henley's Twentieth Century Formulas Recipes Processes" encyclopedia, by Norman W. Henley and others.
Alkaline liquids sometimes used for cleaning gold lace are unsuitable, for they generally corrode or change the color of the silk. A solution of soap also interferes with certain colors, and should therefore not be employed. Alcohol is an effectual remedy for restoring the luster of gold, and it may be used without any danger to the silk, but where the gold is worn off, and the base metal exposed, it is not so successful in accomplishing its purpose, as by removing the tarnish the base metal becomes more distinguishable from the fine gold.
To clean silver lace take alabaster in very fine powder, lay the lace upon a cloth, and with a soft brush take up some of the powder, and rub both sides with it till it becomes bright and clean, afterwards polish with another brush until all remnants of the powder are removed, and it exhibits a lustrous surface.
Silver laces are put in curdled milk for 24 hours. A piece of Venetian soap, or any other good soap, is scraped and stirred into 2 quarts of rain water. To this a quantity of honey and fresh ox gall is added, and the whole is stirred for some time. If it becomes too thick, more water is added. This mass is allowed to stand for half a day, and the wet laces are painted with it. Wrap a wet cloth around the roller of a mangle, wind the laces over this, put another wet cloth on top, and press, wetting and re peating the application several times. Next, dip the laces in a clear solution of equal parts of sugar and gum arabic, pass them again through the mangle, between two clean pieces of cloth, and hang them up to dry thoroughly, attaching a weight to the lower end.
Soak gold laces over night in cheap white wine and then proceed as with silver laces. If the gold is worn off, put 771 grains of shellac, 31 grains of dragon's blood, 31 grains of turmeric in strong alcohol and pour off the ruby-colored fluid. Dip a fine hair pencil in this, paint the pieces to be renewed, and hold a hot flatiron a few inches above them, so that only the laces receive the heat.
Silver embroideries may also be cleaned by dusting them with Vienna lime, and brushing off with a velvet brush.
For gildings the stuff is dipped in a solution of gold chloride, and this is reduced by means of hydrogen in another vessel.
For silvering, one of the following two processes may be employed: (a) Painting with a solution of 1 part of phosphorus in 15 parts bisulphide of carbon and dipping in a solution of nitrate of silver; (6) dipping for 2 hours in a solution of nitrate of silver, mixed with ammonia, then exposing to a current of pure hydrogen.