Masamoto Sohonten KI (Hongasumi White 1) Yanagiba 330 mm with Saya

A yanagiba (柳刃包丁) is a sashimi knife for slicing raw fish. A knife maker's guide says a sashimi knife cuts without breaking the fibres of the flesh, and that it is longer and narrower than other knives because slicing sashimi with crisp edges needs the length.

The whole length goes through one pulling cut. The Sakai cutlery association calls the yanagiba the sashimi knife used mainly in the Kansai region.

Size a yanagiba to the fish you prepare: a knife maker's guide gives 270 to 360 mm for professional use and 240 to 270 mm for home use, with 270 mm at home if you slice larger fish.

The guide says the whole length goes through one pulling cut, so do not choose too short a knife, and at home it points to the size of your board and your work space. We list the yanagiba (柳刃) from 210 to 360 mm, some made for left-handed use.

No. The Sakai cutlery association describes the yanagiba (柳刃包丁) edge as so acute that it cannot be used on hard things such as bones.

For bones the association describes the deba (出刃包丁), whose heel is used to hit them.

Yes, among Shirogami 1, 2 and 3 on Proterial's pages. It describes Shirogami 1 (白紙1号) as having the highest hardness and gives it 1.25 to 1.35% carbon, compared with high hardness and 1.05 to 1.15% carbon for Shirogami 2, and middle hardness and 0.80 to 0.90% carbon for Shirogami 3.

All three are carbon steels that can rust, so wash the knife and dry it after use.

No. Masamoto Sohonten's own history page says Tsukiji Masamoto set up business independently in 1951. Its products and company organisation differ completely from the Sohonten house, and the MASAMOTO trademark is a registered trademark of Masamoto Sohonten, based in Azumabashi.

Both names carry Masamoto, so check which house made the knife: Masamoto Sohonten is the Azumabashi house in Tokyo, and Tsukiji Masamoto is a separate company.

The Masamoto Sohonten history page dates the start of the house to 1866, when the founder returned home and began making cooking knives in Osawa. It says the house was first in the Kanto region to manufacture and sell genuine tempered blade cooking knives in 1874, and it opened in present-day Azumabashi, Sumida-ku, Tokyo in 1890.

The MASAMOTO trademark, No. 20269, was registered in 1903. The history page lists six generations, from the founder Minosuke Matsuzawa to Masahiro Hirano.