Japanese samurai sword crafting.
The fundamental technique of Japanese sword making is the quest to harmonise strength with flexibility. The strength of a blade comes from its hardness and ability to deal armour shattering strikes again and again with its razor sharp edge. The flexibility comes from the blades quality of absorbing the energy of the impact without shattering and leaving its owner without a weapon.
Over centuries, Japanese sword smiths sought the perfect combination of these two attributes in order to produce high quality weapons that could be relied upon on the battlefield.
Eventually the perfect solution was found to be a combination of soft steel surrounded by a harder shield of heat treated steel. A high carbon exterior with a low carbon interior.
Modern swords today are classified as Gendaito. Broadly speaking this identifies blades produced since the Meiji times (1868 onwards). A lot of the expertise and knowledge of sword crafting had been lost in the aftermath of World War Two and blades produced for the officer class at this time were often nowhere near as sophisticated as older examples from previous centuries.
Today, Japanese sword craft is highly specialised art which is again attracting younger members of society into its ranks as the knowledge that was lost during the war years continues to be rediscovered. Japanese swords are highly prized by collectors and connoisseurs around the world for their incredible decorativeness and quality and if you ever get the chance to see an exhibition of any of these fine weapons you should not miss it.