Kiritsuke knife 21cm japanese artisanal Masashi Yamamoto BS1 Black Nashiji

A Japanese knife forged by the incredible Masashi Yamamoto

This Kiritsuke knife is the work of Masashi Yamamoto, a young Japanese blacksmith who is known for making exceptional knives. He is a modern blacksmith trained in the craft by his older brother. He set up his own workshop in 2013, when he felt ready.

Masashi san designs and creates knives that are superb one-offs. Knives are highly prized for the hardness of their blades: the blacksmith achieves this hardness by applying special technical and heat treatments. Although Masashi Yamamoto is a young blacksmith, he has already passed on his skills to two apprentices! He's a blacksmith with a unique style that makes him very charismatic: Masashi is used to blacksmithing in flip-flops, with a cigarette in his mouth!

Top-of-the-range materials for this knife

Your Masashi Yamamoto 21cm kiritsukeJapanese knife is equipped with a blade featuring a typically Japanese San Maï structure. This structure consists of a rigid steel core surrounded by a slightly softer layer of steel folded on either side of the core. The outer layer helps protect the center of the blade, while giving it greater flexibility. This does not mean that the blade becomes flexible in the true sense of the word, but simply that it has greater versatility and is a little less prone to breakage.

Masashi san chose to make the blade core from Aogami #1 steel (also known as Blue Paper Steel #1 or BS1). This is a Japanese steel produced by the world-famous Hitachi steelworks.

This alloy contains a high carbon content of around 1.3%. Carbon is the essential element for increasing the hardness of an alloy, because the harder an alloy is, the longer it keeps its cutting edge. The blade of this knife has a hardness of 63 HRC, proof that its high-performance cutting edge is long-lasting.

Aogami #1 steel is quite expensive due to its composition and difficult handling. Indeed, if the blacksmith who works it is not an expert, it can generate significant and costly losses. Masashi Yamamoto is one of the experts in working with this alloy.

The Aogami #1 steel core is then coated withsoft iron, an alloy enriched with iron ore. The layer of this alloy sandwiches the core by being folded on either side. The San Maï layers are formed, the core is protected and its hardness is balanced. Note that the blade is enriched with carbon and iron, making it oxidizable. This is why this knife requires the utmost care on your part (all our tips are available further down this page).

Note that Masashi Yamamoto knives have a finer point than the average knife. In fact, the thickness of the blade narrows as you reach its tip, making it more flexible and therefore easier to cut, with a more pleasant, natural feel in use. This is further proof of this outstanding blacksmith's expertise. However, be careful not to press too hard, as flexibility has its limits!

A Black Nashiji finish has been applied to the blade. This technique gives the blade an authentic rustic appearance, giving the impression that it has not been polished and has retained its black hue. The Black Nashiji finish is reminiscent of a brute forge finish and has given its name to the knife range.

The knife's octagonal-shaped handle provides an ideal, comfortable grip. The handle hugs the palm of your hand, reducing the feeling of fatigue associated with use. What's more, the handle shape is suitable for both right- and left-handed users.

The handle is made from quince, a durable wood resistant to humidity and temperature variations. Quince is characterized by its light color.

A dark ebony Bolster completes the handle, providing an elegant contrast to the light color of the quince. The two woods are separated by a fine white micarta ring.

Caring for this carbon Japanese knife

As mentioned above, your kiritsuke is an oxidizable knife. For this reason, it should not be left in the sink waiting to be cleaned, nor should it be put in the dishwasher.

Your knife should be washed by hand in lukewarm water, using a mild soap and a non-abrasive sponge. Take care not to get the handle wet during washing. Then wipe the knife dry immediately, making sure to remove all traces of moisture. Finally, store the knife in a dry place.

Due to its composition, the blade may change color slightly over time. This is absolutely normal! The steel of which it is made is naturally reactive to elements such as humidity in the air or the acidity of certain foods.

We recommend applying a littleoil to the blade with a soft cloth from time to time. This provides extra protection and nourishment.

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