白钢（Shirogami）：

• 优点：极其锋利，快速磨利
• 缺点：需要频繁维护
• 最适合：重视切割精度和易磨性的专业人士

苍蓝钢铁（青神）：

• 优点：刀刃保持时间更长，耐磨性更好
• 缺点：较难磨锐，较脆
• 最适合：注重耐用性的重型切割

刀具虽然外表呈银色，但磨刀时产生的磨浆会变黑。这是因为磨浆中含有碳，而碳是赋予刀具硬度的关键成分。

钢材的硬度分为1 号、 2 号和3 号，数字越小表示硬度越高。例如， 1 号钢材硬度最高，刀刃也最锋利。2号钢材和3 号钢材的硬度和锋利度依次降低，但对于大多数用途来说，它们仍能保持足够的锋利度。

Does More Carbon Mean a Sharper Knife?

Most knife enthusiasts start with the same assumption:
More carbon → harder steel → sharper knife.

It sounds logical. But spend time with Japanese knife culture, and that equation starts to crack.

High-carbon steels contain more carbide particles — microscopic hard structures that give a blade bite. Great for gripping tomato skin or scoring fish. But at a cellular level, that same aggression tears food apart rather than slicing cleanly through it.

Finer-grained, moderate-carbon steels behave differently. Their edges glide — separating food along natural planes, preserving texture and flavor.

In Japanese cuisine, where a single ingredient can be the entire point of a dish, that difference is not subtle. It's everything.

Bite and smoothness are both forms of sharpness. They just do different things.

Harder steel is not easier to sharpen — it's less forgiving.

Push the angle slightly off on a high-carbon blade, and you don't get a dull edge. You get micro-chipping, uneven geometry, a tiny irregular saw masquerading as a sharp knife.

Moderate-hardness steels — like White Steel (Shirogami) — respond to the whetstone predictably. A skilled sharpener can bring them to an extraordinary edge, often surpassing what a harder steel achieves in less careful hands.

In traditional Japanese craftsmanship, the sharpener has always been considered as important as the steel itself.

Yes, higher carbon generally means longer edge life — in traditional carbon steels.

But in stainless steels, the relationship flips. Some lower-carbon alloys, engineered with fine grain structures, hold a refined edge longer than harder, carbide-heavy alternatives — because they degrade more slowly and more evenly.

Which is why serious knife makers don't talk about carbon content alone. They think about grain structure, heat treatment, and — critically — what the knife is actually for. A deba for breaking down whole fish demands something completely different from a gyuto for fine vegetable work.

For centuries, Japanese craftsmen sharpened exclusively on natural whetstones. Those stones had a natural affinity for fine-grained steels — White Steel sharpened quickly and beautifully on them.

Blue Steel (Aogami), with its added chromium and tungsten, was harder and more wear-resistant, but fought the stone. Getting it truly sharp required considerably more skill and time. For generations, White Steel was considered the gold standard for edge refinement — despite its lower carbon content.

Modern synthetic and diamond stones changed this. Harder steels can now be refined with precision that wasn't previously possible, opening the field to materials that would have been impractical a generation ago.

Higher carbon gives you: aggressive bite, longer edge life, durability.
Finer-grained or moderate-carbon steels give you: smooth cuts, flavor preservation, an edge that's easier to bring back.

Neither is objectively better. They're optimized for different things.

The question serious Japanese knife culture has always asked isn't "which steel is hardest?"

It's "what kind of cutting do you want to do?"

Because sharpness isn't a number on a spec sheet.
It's the relationship between blade, food, and the hands that maintain it.