Katana Radiant Wave Maru Blade Kōrin Koshirae 光浪

Clay Tempered Full Tang Shinken (真剣) | Radiant Wave Katana: TangGu (湯谷) Maru Blade (丸造) + TangGu (湯谷) Kōrin Koshirae (光浪拵)

The uchigatana-style koshirae (打刀拵) blends traditional artistry with refined functionality. The blade is forged in Maru-zukuri (丸造) style from proprietary high-carbon steel, a monosteel construction that ensures consistent strength and edge retention. The blade shows no visible hada (鍛肌なし). A Suguha with slight Midare (小乱れ交じり直刃) hamon emerges through clay tempering (覆土焼入れ).

The saya (鞘) is finished in Kin-nashiji lacquer (金梨子地塗), a golden pear-skin style with shimmering elegance. Koiguchi, kurigata, and kojiri are made of polished buffalo horn. A yellow cotton sageo (下緒), tightly woven, completes the scabbard.

The tsuka (柄) is wrapped in yellow silk ito over natural white samegawa (鮫皮), reinforced with hishigami (菱紙). The menuki (目貫) are crafted from white copper (白銅) with blackened patina, carved in delicate floral motifs (花卉). The fuchi and kashira (縁頭) are brass with blackened patina (煮黒仕上げ), hand-carved in katakiribori (片切彫) style featuring wave designs (海浪). The tsuba (鍔) is a mokko-gata (木瓜形) iron guard, also blackened and carved in katakiribori style with flowing wave motifs (海浪).

TangGu (湯谷) Maru Blade

This blade is hand-forged (Tezukuri / 手作り) from high-carbon steel (高炭素鋼) in a monosteel construction called Maru-zukuri (丸造).

Blade Forging Details

• Blade Name: TangGu Traditionally Forged Maru Blade (丸造)
• Forging Method: Maru-zukuri（丸造）style with a single piece of high-carbon steel. Clay tempering (覆土焼入れ) creates a hardened edge, softer spine, and visible hamon.
• Materials: Proprietary high-carbon steel（自家製高炭素鋼）refined for hardness, toughness, and grain control.
• Purpose: Suitable for Kenjutsu and Tameshigiri (test cutting) practice, collection, and display. Unsharpened blades are available for Iaido upon request.

Blade Specifications

• Blade Length (Nagasa刃長): Approx 73 cm
• Tang Length (Nakago 茎長): Approx. 24 cm
• Width at Base (Motohaba 元幅): Approx. 31 mm
• Thickness at Base (Motokasane 元重): Approx. 6 mm
• Width at Tip (Sakihaba 先幅): Approx. 22 mm
• Thickness at Tip (Sakikasane先重): Approx. 4 mm
• Kissaki Length (Tip 切先長): Approx. 33 mm
• Mekugi-ana (Peg Hole 目釘穴): 1

Blade Characteristics

• Shape: Shinogi-zukuri (ridged blade 鎬造), Iori-mune (flat ridged spine 庵棟), Chū-kissaki (Medium-sized tip 中切先)

• Forging Pattern (Hada 鍛肌): None (鍛肌なし) — forged from monosteel with uniform grain.
• Temper Line (Hamon 刃文): Suguha with slight Midare（小乱れ交じり直刃）— formed by clay tempering (覆土焼入れ), mostly straight with subtle undulations.

Special Features and Workmanship

Hi (Groove) Engraving

• Type: Hi-Nashi (樋なし)
• Processing Range: None (No bohi) – Solid blade for added weight and strength

Polishing Work

• TangGu Polishing Levels:
  • Highest-grade shaping polish 最上・成形研磨 
  • Superior rough polish 最上・下研ぎ 
  • Detailed final polish 最上・仕上げ研ぎ 
• Key Features:
  • The blade is forged in Maru-zukuri（丸造）style from a single piece of proprietary high-carbon steel. Clay tempering（覆土焼入れ）produces a Suguha with slight Midare（小乱れ交じり直刃）hamon with a brightened edge (Hashiro / 刃白).

Fittings and Mountings

Blade Fittings

• Tsuba (Handguard 鍔): Mokko-gata (木瓜形) iron tsuba with blackened patina (煮黒仕上げ), hand-carved in katakiribori (片切彫) style featuring wave motifs (海浪).
• Fuchi-Kashira (縁頭): Brass with blackened patina (煮黒仕上げ), hand-carved in katakiribori (片切彫) style with wave motifs (海浪).
• Menuki (目貫): White copper (白銅) menuki with blackened patina, decorated with floral motifs (花卉).
• Habaki (鎺): Hand-forged brass with antique finish.
• Samegawa (Ray Skin 柄鮫): Genuine ray skin in natural white.
• Handle Wrapping (Tsuka-maki 柄巻): Yellow silk ito, tightly wrapped in hineri-maki (捻巻) style.

Saya and Accessories

• Saya (Scabbard 鞘): Traditional-style design reinforced with water buffalo horn at the koiguchi (mouth), kojiri (end), and kurigata (cord knob).
• Saya Lacquer (鞘塗): Kin-nashiji (金梨子地塗) lacquer with a luminous golden pear-skin finish, shimmering with refined elegance.
• Sageo (Cord 下緒): Yellow cotton sageo, tightly woven.

Measurements

• Blade Weight: Approx. 0.65 kg
• Sword Weight (without Saya): Approx. 1.0 kg
• Total Weight: Approx. 1.3 kg
• Overall Length: Approx. 100 mm