Yasuki Steel

  • The soul of a great knife lies in its steel.

    Have you ever wondered what makes Japanese knives so sharp, so precise, and so loved by chefs worldwide?
    Behind their brilliance lies Yasuki Steel—a legendary material born from centuries of tradition, refined through the spirit of Japanese craftsmanship.

    This video takes you inside the world of Yasuki Steel: its history rooted in Tatara ironmaking, its role in shaping the famed Sakai knives, and its uncertain future.
    Discover why this extraordinary steel is not just a material—but the soul of Japanese blades.

  • Have you ever struggled with a dull kitchen knife? The sharpness of a blade shapes not only the quality of your dishes but also the joy of cooking itself. At the heart of Japan’s world-renowned Sakai Knives lies a legendary material: Yasuki Steel. This steel embodies more than performance—it represents the very essence of Japanese craftsmanship.

  • Origins of Yasuki Steel

    Yasuki Steel, produced at Hitachi Metals’ Yasugi Works in Shimane Prefecture, is one of Japan’s most celebrated steels. Its roots trace back to Tatara ironmaking, an ancient method using high-purity sand iron. For centuries, this steel has supported Japan’s swordsmithing and blade-making traditions.

    Over time, Yasuki Steel evolved into several series, each with unique characteristics:

  • 1. White Steel (Shirogami)

    Extremely hard and capable of producing razor-sharp edges, perfect for precision knives.

  • 2. Blue Steel (Aogami)

    Enhanced with tungsten and chromium, offering greater durability and longer edge retention.

  • 3. Ginsan

    A modern high-carbon stainless steel that combines sharpness with rust-resistance, ideal for daily use.

  • This versatility makes Yasuki Steel the material of choice for master bladesmiths worldwide.

  • Sakai Knives: Tradition Forged in Steel

    Sakai City in Osaka has been producing blades for over 600 years. The unmatched quality of Sakai Knives comes from the perfect marriage of Yasuki Steel and the artisans’ skill.

    Unlike mass-produced knives, Sakai blades undergo a meticulous process: forging, heat treatment, and final sharpening are all performed by hand. This process unlocks the steel’s full potential, creating knives that are exceptionally sharp, durable, and beautiful.

    As one Michelin-starred chef put it:

    “Sakai Knives are not just tools. They are instruments that breathe life into culinary creations and symbolize the spirit of Japanese craftsmanship.”

  • Why Yasuki Steel Matters Today

    hand, adorned with subtle patterns, and finished with precision—is a work of art born from centuries of skill.

    Yet this tradition now faces uncertainty:

    1. Corporate Transition: In 2023, Hitachi Metals was acquired by Bain Capital and reorganized under a new company, Proterial. This has raised concerns that profit-driven policies may overshadow cultural heritage.
    2. Small Market Size: High-grade steels like Yasuki account for only a tiny portion of the metal industry, making their production vulnerable.
    3. Changing Priorities: Large corporations increasingly view specialty steels as “unprofitable,” threatening their long-term continuation.


    Without action, we may one day lose access to this extraordinary steel that has defined Japanese craftsmanship for generations.

  • Preserving a Brilliant Tradition

    So, what can we do? The answer is simple: use it, share it, and pass it on. By cooking with Yasuki Steel knives, experiencing their sharpness, and spreading their story, we help preserve this tradition.

    Owning a knife made from Yasuki Steel is not just about having a tool. It means holding a piece of Japan’s history, culture, and craftsmanship in your hands.

    Now is the time to take action—before this brilliant tradition fades.

    Yasuki Steel is the ultimate expression of Japanese craftsmanship. Experience its sharpness, share its story, and help protect its future.

FAQ About Yasuki Steel

Hitachi Yasuki Steel is a premium brand of steel manufactured by Hitachi Metals at its Yasuki plant in Shimane Prefecture, Japan. This region has a long-standing tradition of steelmaking, once famed for producing steel through the ancient Tatara smelting method. Today, Hitachi continues this legacy with modern metallurgical techniques, producing high-grade steels widely used in Japanese kitchen knives.

There are two main types of Yasuki steel used in traditional Japanese knives:

・White Steel (Shirogami)
Made from 100% high-purity iron sand (satetsu), this steel contains very few impurities. It’s known for excellent sharpness and ease of sharpening.

・Blue Steel (Aogami)
Based on White Steel, but with added chromium (Cr) and tungsten (W), which improve its toughness and edge retention. It’s more resistant to wear but slightly harder to sharpen than White Paper Steel.

These steels are favored by professional chefs for their balance of cutting performance and traditional forging potential.

Tamahagane is a traditional Japanese steel also made from iron sand but smelted in a Tatara furnace using time-intensive methods. It contains natural inclusions that create unique patterns when forged, contributing to the beauty and strength of Japanese swords.

While both Tamahagane and Yasuki steel share similar raw materials, Yasuki steel is industrially refined for modern performance, making it more suitable for professional-grade kitchen knives.

Hitachi Ltd. sold Hitachi Metals as part of a strategic shift to focus on core businesses like digital and IT services. The steel division, while highly respected, was considered less aligned with this new direction. The sale follows Hitachi’s broader trend of streamlining its operations through divestitures and spin-offs.

Absolutely. Yasuki steel is one of the most trusted materials in the world of Japanese cutlery. Its purity, hardness, and ability to hold a fine edge make it ideal for culinary professionals seeking high-performance tools.

Yasuki Steel: The Heart of Japanese Knives—Its Current State and Future Prospects

This article explores the current status and future outlook of Yasuki Steel, the legendary material behind traditional Japanese knives, in light of the 2023 transition from Hitachi Metals to Proterial. It highlights the ongoing but uncertain production of White Steel and Blue Steel, the introduction of new high-performance stainless steels (YBS1/YBS2), and what these changes mean for knife makers, users, and collectors around the world. As the industry stands at a turning point, understanding steel is more essential than ever.

Yasuki Steel: The Heart of Japanese Knives—Its Current State and Future Prospects

Is ZDP189 No Longer Available? — The Truth Behind the Legendary Steel

Once hailed as a “dream material,” ZDP189 is now fading from the spotlight.This article explores the corporate strategy behind its disappearance and the potential discontinuation of this legendary steel. It’s a must-read for collectors and craftsmen alike.

Is ZDP189 No Longer Available? — The Truth Behind the Legendary Steel

The Soul of Craftsmanship

  • Steel, Spirit, and the Future of Japanese Knives

    The brilliance of Japanese knives does not come from technique alone. At their core lies the spirit of the craftsman—and the steel that forms the blade.

  • For centuries, artisans have relied on steels such as White Steel (Shirogami) and Blue Steel (Aogami), valued for their purity and sharpness. These traditional carbon steels embody the very essence of Japanese bladesmithing. Their continued production allows us to carry forward the legacy of our ancestors.

  • In modern times, **Hitachi Metals—now Proterial—**has supported this tradition by providing high-grade steels like Ginsan (Silver #3) and the high-performance ZDP-189. These steels, refined to extraordinary purity, have enabled us to forge blades that combine sharpness, durability, and beauty.

  • Yet today, there are whispers of uncertainty. Some specialty steels—such as ATS-34, ZDP-189, and Ginsan—have been rumored to face reduced availability or even production concerns. Likewise, even for White and Blue Steel, voices in the craft world quietly wonder how long these carbon steels will continue to be produced in an era increasingly dominated by stainless alloys and globalized supply chains.

  • As artisans, we cannot control the tides of industry. But what we can do is pour our spirit into every blade, ensuring that—no matter the steel—we create knives that carry the soul of Japanese tradition.

  • The steel may one day change, but the spirit of the craftsman will never disappear. With each hammer strike and every pass of the whetstone, we keep alive not just a material, but a philosophy: that a knife is more than a tool—it is a bridge connecting the wisdom of the past with the hopes of the future.
Sakai Traditional Craftsmen Collection

KIREAJI's Three Promises to You

  • japanese_knife_made_in_Sakai

    1. Forged in the Legacy of Sakai

    From Sakai City—Japan’s renowned birthplace of professional kitchen knives—each blade is crafted by master artisans with over six centuries of tradition. Perfectly balanced, enduringly sharp, and exquisitely finished, every cut carries the soul of true craftsmanship.

  • 2. Thoughtful Care for Everyday Use

    Every knife includes a hand-fitted magnolia saya for safe storage. Upon request, we offer a complimentary Honbazuke final hand sharpening—giving you a precise, ready-to-use edge from day one.

  • 3. A Partnership for a Lifetime

    A KIREAJI knife is more than a tool—it is a lifelong companion. With our bespoke paid aftercare services, we preserve its edge and beauty, ensuring it remains as precise and dependable as the day it first met your hand.