Great importance has always been attached by Japanese experts to the patina of metal used for artistic chiselling. It was mainly for the sake of their patina that value attached to the remarkable alloys _shakudo_ (3 parts of gold to 97 of copper) and _shibuichi_ (1 part of silver to 3 of copper). Neither metal, when it emerges from the furnace, has any beauty, shakudo being simply dark-coloured copper and shibuichi pale gun-metal. But after proper treatment[2] the former develops a glossy black patina with violet sheen, and the latter shows beautiful shades of grey with silvery lustre. Both these compounds afford delicate, unobtrusive and effective grounds for inlaying with gold, silver and other metals, as well as for sculpture, whether incised or in relief. Copper, too, by patina-producing treatment, is made to show not merely a rich golden sheen with pleasing limpidity, but also red of various hues, from deep coral to light vermilion, several shades of grey, and browns of numerous tones from dead-leaf to chocolate. Even greater value has always been set upon the patina of iron, and many secret recipes were preserved in artist families for producing the fine, satin-like texture so much admired by all connoisseurs. Methods of Chiselling. In Japan, as in Europe, three varieties of relief carving are distinguished--_alto_ (_taka-bori_), mezzo (_chuniku-bori_) and _basso_ (_usuniku-bori_). In the opinion of the Japanese expert, these styles hold the same respective rank as that occupied by the three kinds of ideographic script in caligraphy. High relief carving corresponds to the _kaisho_, or most classical form of writing; medium relief to the _gyosho_, or semi-cursive style; and low relief to the _sosho_ or grass character. With regard to incised chiselling, the commonest form is _kebori_ (hair-carving), which may be called engraving, the lines being of uniform thickness and depth. Very beautiful results are obtained by the kebori method, but incomparably the finest work in the incised class is that known as _kata-kiri-bori_. In this kind of chiselling the Japanese artist can claim to be unique as well as unrivalled. Evidently the idea of the great Yokoya experts, the originators of the style, was to break away from the somewhat formal monotony of ordinary engraving, where each line performs exactly the same function, and to convert the chisel into an artist's brush instead of using it as a common cutting tool. They succeeded admirably. In the kata-kiri-bori every line has its proper value in the pictorial design, and strength and directness become cardinal elements in the strokes of the burin just as they do in the brushwork of the picture-painter. The same fundamental rule applied, too, whether the field of the decoration was silk, paper or metal. The artist's tool, be it brush or burin, must perform its task by one effort.