Ginsan steel, also known as Silver #3 or G3, is a stainless steel made by Hitachi Special Steel in Japan, containing 1.02% carbon and 13.75% chromium, and it is used in Japanese knives because it combines the sharpness and ease of sharpening of carbon steel with the rust resistance of stainless steel. It is a fine-grained steel that takes a very sharp edge, and at a hardness of 60-62 HRC, it offers a practical balance of edge retention and sharpenability for everyday kitchen use.

The name "Ginsan" (銀三) literally means "silver three," referring to its Silver #3 designation. Its moderate chromium content makes it far less reactive than carbon steels, so it won't discolor or rust as quickly, while its carbon content keeps the edge keen and responsive on the stones. For home cooks and professionals who want a stainless knife that still feels like a traditional Japanese blade, Ginsan is a common middle ground.

The Tetsujin Ginsan Kasumi is a budget-friendly knife line forged by blacksmith Toru Tamura and sharpened by Naohito Myojin, designed for professional chefs, students, and first-time buyers who need thin geometry for effortless slicing without the cost of premium steel.

This line prioritizes a sturdy feel and a thin edge that glides through ingredients, making it a practical daily driver for those who cut frequently but want to avoid the high price tag of top-tier Japanese steels. While the steel itself is not classified as premium, the construction delivers reliable performance for the price point, fitting the needs of anyone from a culinary student to a working chef looking for a durable, no-nonsense tool.