The process of plating with an alloy first of zinc and silver, and more recently with one of cadmium and silver, introduced by the London Metallurgical Company, has been recently described in our columns, and therefore no lengthy exposition is now necessary. Since we last spoke of it, however, it has reached a more advanced stage of commercial utility, and is being worked on a tolerably large scale with satisfaction to users who include firms well able to judge what constitutes good work in electro-plating, and little likely to be attracted by any novelty that is not possessed of solid recommendations. There is one fresh development of the process that claims some comment, namely, the utilisation of the “Arcas” alloy for making articles of standard silver as well as plated goods. The merits of the alloy of cadmium and silver of course do not depend upon the fact that it has hitherto been deposited on plated articles electrolytically, and as its hardness and freedom from tendency to tarnish, and the ease with which it is cleaned, are valuable for the purposes of the silversmith as distinct from the plater, a curious trade has arisen in goods of standard silver being sent to the London Metallurgical Company to be plated with “Arcas.” So Hibernian a proceeding could not fail to suggest to the brutally practical Saxon that if the coating of standard silver was to be “Arcas’’ the whole of the mass might as well be made of it. One would have expected, bearing in mind the anomalous character of our legislative enactments, especially where they touch technical affairs, that it would have been found impossible to get goods containing the amount of silver present in the sterling metal —92.5 per cent.—but with the balance composed of any other metal than copper, the use of which has been sanctioned by long custom, passed as standard, but no such difficult appears to exist, and provided that the metal sent to be assayed and stamped contain the specified quantity of silver it is immaterial whether the remainder be copper, cadmium zinc, or any other preferred by the vendor. Consequently there are now being made articles of solid “ Arcas”’ silver, hall-marked, and containing 92.5 per cent. of actual silver which are as valuable intrinsically as ordinary standard silver, and free from many of the defects which go far to make one of the metals best fitted for domestic use by those who care for the small refinements of life, a constant trial to the mistress and tribulation to the maid.
Source: The Engineer - 16th December 1892