With their latest set of US exclusive releases, Grand Seiko turns their attention to the katana, a Japanese sword, crafted from steel, that has become a symbol of Japanese culture across the world. There is a real art to creating a katana blade, and with these new watches, Grand Seiko is drawing inspiration from that centuries old process in much the same way they?ve built a cottage industry around watches that pull in aesthetic inspiration from the changing seasons and the natural world. What really links the katana to these watches though, and it?s something absent from the nature inspired dial designs, is a focus on craft. A katana blade is formed by heating iron sand in a special furnace called a tatara, with the melted sand becoming the steel known as tamahagane, a traditional Japanese material. Layers of metal are stacked individually, one on top of the other, heated, forged, folded, and cooled with water until the core of the sword takes shape. Eventually the blade is polished, taking on the familiar edge you?d expect, in a process that is not too dissimilar from putting a mirror shine on a Grand Seiko case, at least in the sense that both are done by hand by highly skilled craftspeople. 
There are three releases in total in this mini collection inspired by the katana. The SBGA489, inspired by kawagane, the outer, sharp edge of a katana blade, has a black dial with a lightly stippled texture modeled after tamahagane steel. The SBGA491 features the same dia...