3218. To Frost Polished Silver

3218.    To Frost Polished Silver. To produce a frosted surface on polished silver, use cyanide of potassium with a brush. The silver should not be handled during the process, but held with pliers made of lance-wood or boxwood. The proportion should be 1 ounce dissolved in 1/2 pint of water. It is very poisonous.

3219. To Oxidize Silver

3219.     To Oxidize Silver. A very beautiful effect is produced upon the surface of silver articles, technically termed oxidizing, which gives the surface an appearance of polished steel. This can be easily effected by taking a little chloride of platinum, prepared as described in the next receipt, heating the solution and applying it to the silver when an oxidized surface is required, and allowing the solution to dry upon the silver. The darkness of the color produced varies according to the strength of the platinum solution, from a light steel gray to nearly black. The effect of this process, when combined with what is termed dead work, is very pretty, and may be easily applied to medals, giving scope for the exercise of taste. The high appreciation in which ornaments in oxidized silver are now held, render a notice of the process followed interesting. There are two distinct shades in use - one produced by chloride, which has a brownish tint, and the other by sulphur, which has a blueish-black tint. To produce the former, it is only necessary to wash the article with a solution of sal-ammoniac; a much more beautiful tint may, however, be obtained by employing a solution composed of equal parts of sulphate of copper and sal-ammoniac in vinegar. The fine black tint may be produced by a slightly warm solution of sulphuret of potassium or sodium. (Dr. Ellsner.)

3220. To Prepare Nitro-Muriate (Chloride) of Platinum

3220. To Prepare Nitro-Muriate (Chloride) of Platinum. The nitro-muriate of platinum is easily prepared: Take 1 part nitric acid, and 2 parts hydrochloric (muriatic) acid; mix together and add a little platinum ; keep the whole at or near a boiling heat; the metal is then dissolved, forming the solution required.

3221. To Make a Silver Tree

3221.    To Make a Silver Tree. Dissolve 20 grains nitrate of silver in 1 fluid ounce of water in a phial, and add 1/2 drachm pure mercury. Arrange the zinc as for the lead tree. Very brilliant and beautiful.

3222. To Clean Silver after it is Soldered

3222.    To Clean Silver after it is Soldered. Make it just red hot, and let it cool; then boil it in alum water, in an earthen vessel, and it will be as clean as when new.

3223. Belgian Burnishing Powder

3223.     Belgian Burnishing Powder.

A burnishing powder in use in Belgium is composed of 1/2 pound fine chalk, 3 ounces pipe clay, 2 ounces white lead, 3/4 ounce magnesia (carbonate), and the same quantity of jeweler's rouge.