The surface is Shakudo mikagi ji (赤銅磨地) or a polished shakudo finish. The colour is a deep black and as fine as any Gotô work of that time. The design is carved in kibori (毛彫) and the gold treatment is Kin keshikomi zôgan (金消込象嵌). Keshikomi zôgan is an inlay technique where, after the design has been incised or carved into the ground or surface, powdered gold, silver or another selected fine metal, having been made into an amalgam by combining it with mercury (this is easily accomplished with all non-ferrous materials) is forced into the incised pattern in the ground. This is then heated which inturn evaporates the mercury, depositing the coloured metal on the ground, forming the inlay.
The effect of the rich gold over the jet black gloss of the shakudo is truly wonderful.
Some of the most intricate detail can be achieved with this method and it is amazing that such detail was accomplished in a time before microscopes. It is interesting read in Sôken Kodôgu Yôgo to Meishô no Kaisetsu that many tsuba/kodogu lovers do not approve of techniques like this, and believe that this scientifically clever but artificial and is more a chemical trick than true art.
The dimensions are Fuchi: 38.1 mm x 8mm, Kashira: 33.9mm x 19.4mm
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