Page:Brinkley - Japan - Volume 7.djvu/261

 Speaking generally, a greyish patina and silvery lustre are regarded as the most attractive features of shibuichi, but Soyō's compound presents even choicer qualities. In the course of years the finest kind of shibuichi develops a peculiar lustrous dappling, like the marking of a tiger's skin or the ground of aventurine (nashi-ji) lacquer." It is unnecessary to reproduce here any analytical table of shibuichi. If to what has been already said the fact be added that it contains a small quantity of gold—from 0.08 to 0.12 per cent—its composition is sufficiently described. Mr. Gowland says of shibuichi:—

The value of this alloy in decorative metal work is, like that of shakudo, entirely dependent on its patina. It possesses no special beauty when cast, its colour being that of pale gun-metal, or a common pale bronze; but when its surface is subjected to appropriate treatment, it assumes a patina of charming shades of grey, which gives it an unique position among art alloys. No other affords the artist such a delicate, unobtrusive, and effective ground for inlaid designs of gold, silver, or other metals. It was not known to the Japanese in medival times. In fact, it does not appear to have been used until much later than shakudo. The descriptions given of the ornamental appendages of historical swords even as late as the seventeenth century do not mention it, and the first record we have of the alloy only dates from the beginning of the eighteenth century (1706 ), when it was used in the Government Mint for the preparation of debased silver bars, termed chogin (trade silver), which were used for commercial purposes. There are several examples of its use in sword-guards about the same date, but it seems then to have been chiefly employed as a substitute for a richer alloy, a pure silver surface having been given to it by the process already described, and not the fine grey patina of later times. The patina is produced by precisely the same operations which are practised for shakudo, the solution in which the objects are boiled having the same composition as