The History of Yasugi Steel (安来鋼)

The roots of Yasugi steel go back centuries to the Tatara smelting tradition of the Chūgoku region (western Honshū). The Yasugi area in Shimane Prefecture was an important center for producing tamahagane, the traditional steel used for swords, woodworking tools, and specialized cutlery. Tatara steelmaking used iron sand (“satetsu”) and charcoal to create pure, high-carbon steel. This long tradition established Yasugi’s reputation for high-quality metalworking.

In 1907, Yasugi Works (安来工場) was founded by Hitachi Metals predecessors to industrialize high-quality tool steels. Their goal was to combine traditional tamahagane quality with modern metallurgical consistency. During this period the term “Yasugi-hagane” (安来鋼) began to refer not just to location, but to a brand of premium tool steel.

By the mid-20th century, Hitachi Metals created modern standardized steels inspired by traditional tamahagane characteristics.

These include:

White Paper Steel (Shirogami / 白紙鋼)

• Very pure carbon steel

• Labels: #1, #2, #3

• Closest to traditional tamahagane in composition purity

Blue Paper Steel (Aogami / 青紙鋼)

• Carbon steel with added chromium and tungsten

• More wear resistance

• Types: Blue #1, Blue #2, Blue Super

Yellow Paper Steel (Kigami / 黄紙鋼)

• Lower-carbon, more economical cutlery/tool steel

The “paper” names came from the colored wrapping paper used at the Yasugi Works to distinguish each alloy.

By the 1960s–2000s, Yasugi steels became world standards for knives, woodworking tools, chisels, plane blades, and specialty cutting instruments. Japanese knifemakers popularized Shirogami and Aogami steels among international collectors and chefs.“Yasugi Steel” became synonymous with high-purity, high-performance tool steel.

Yasugi steel is highly esteemed due to its exceptional purity in its composition. (very low phosphorus and sulfur), tight metallurgical tolerances, excellent edge-holding and sharpness, tradition dating from the Tatara era. It truly represents the blending of Japanese craft heritage and modern steelmaking science.

How does Yasugi Steel Relates to Tamahagane

Both tamahagane and Yasugi Steel come from the same historical steelmaking region, namely Yasugi (安来) in Shimane Prefecture which is the homeland of tatara smelting, the source of Japan’s highest-quality traditional steel. So the connection starts with geography and heritage

The both use the same “purity ideal” but each under different methods. Traditional tamahagane is produced in a clay tatara furnace using iron sand and charcoal. It is celebrated for it's high carbon, very low impurities and is excellent for sharp cutting tools (swords, tools).

Yasugi Steel was created in the 20th century to replicate the functional qualities of tamahagane using modern metallurgy consisting of a controlled carbon content, ultra-low sulfur and phosphorus, uniform grain size and mass-production consistency. Yasugi Steel used tamahagane’s performance philosophy but industrialized.

Among all Yasugi steels, 白紙鋼 (Shirogami / White Paper Steel) is the closest modern equivalent to tamahagane. You are asking yourself why?

• No alloy additives

• Extremely pure carbon steel

• Very fine grain

• Capable of extremely sharp, hard edges

• Difficult to forge → just like tamahagane

Many Japanese blacksmiths describe Shirogami #1 and #2 as “refined tamahagane”.

As sword production declined and toolmaking increased, modern makers needed a more consistent steel, easier-to-control heat treatment, available in larger quantities and less variability than tatara-made batches.

So Hitachi Metals created the Yasugi Steel lineup to give toolsmiths a reliable modern steel that still preserved the Japanese forging traditions, traditional edge feel and historical material identity. It is not tamahagane, but it is the direct lineage.

In short,

• Tamahagane = traditional, handmade, variable steel from a tatara.

• Yasugi Steel = modern, industrial steel designed to reproduce and surpass tamahagane’s best qualities with scientific consistency.