Shibuichi (四分一) is a historically Japanese copper alloy, a member of the irogane class, which is patinated into a range of subtle greys and muted shades of blue, green, and brown, through the use of niiro processes, involving the rokushō compound.
Shibuichi (四分一) is a historically Japanese copper alloy, a member of the irogane class, which is patinated into a range of subtle greys and muted shades of blue, green, and brown, through the use of niiro processes, involving the rokushō compound.