Kasumi Rainbow

A work of art, a masterpiece of the art of fire.

Kasumi Rainbow, forged by Takeshi Saji exclusively for Haiku International, is an exceptional knife in more ways than one. A true feat of craftsmanship, it is considered to be the first coloured Damascus knife. Its manufacture relies on an extremely complex layering process, made particularly delicate by the differing melting points of the materials used. The difficulty lies in the simultaneous forging of the two steel layers, which must fuse perfectly under the master blacksmith’s hammer. There are no mechanical guides here: everything is done by eye and by hand. Takeshi Saji, a master craftsman honoured by the Japanese Ministry of Industry and Trade, is today the only person to master this technique. Only twenty examples of each model are produced each year ! 

The name ‘Rainbow’ refers to its unique visual appearance, created by the combination of two components: copper and nickel. The coppery and golden hues arise from the combination of copper and nickel, forged around a core of V-Toku 2 steel from Takefu Special Steel. Nineteen layers are forged on each side of the core, making a total of thirty-eight layers. 

V-Toku 2, comprising approximately 1.1 per cent carbon and enriched with 1.25 per cent tungsten, can achieve an exceptional hardness of up to 64 HRC, the maximum for steel in this category. V-Toku 2 contains little chromium, which promotes remarkable cutting performance whilst remaining relatively easy to maintain.

No two blades are alike. To enhance this harmony, we have chosen to pair it with a handle crafted from precious rosewood, whose deep hues echo the coppery glints of the blade. Its varnished finish enhances the wood’s natural contrasts and highlights the richness of its grain. The handle’s octagonal profile, a classic feature of Japanese design, lends balance, simplicity and elegance to the whole.

Kasumi Rainbow is not only an exceptional knife : it is the embodiment of a craft that has become exceedingly rare, where each blade bears witness to the interplay between fire, material and the master blacksmith’s skill.