Shibuichi

Shibuichi is a Japanese alloy of copper and silver, typically with a silver content of 25% or higher. The name "shibuichi" translates to "four-to-six," referring to a historical ratio of 4 parts silver to 6 parts copper, though modern usage often involves higher silver percentages. This alloy is prized for its unique patina, which can range from a dark, almost black hue to various shades of grey and brown depending on the treatment.

The development of shibuichi is closely linked to the art of Japanese metalworking, particularly in the creation of decorative elements for swords and other objects. It was often used for inlay work, such as *tsuba* (sword guards), *menuki* (ornaments under the sword's hilt), and other fittings. Its ability to accept a wide range of patinas allowed artists to create intricate designs and contrast with other metals like shakudō, another copper-based alloy known for its dark blue or black patina. The subtle coloration and workability of shibuichi made it a versatile material for skilled artisans. Today, shibuichi continues to be used by contemporary artists and craftspeople for jewelry and decorative objects.