Katana Crimson Water Maru Blade Hijin Koshirae 赤水 | TangGu Sword

Shinken (真剣) | Crimson Water Katana: TangGu (湯谷) Maru Blade (丸造) + TangGu (湯谷) Hijin Koshirae (緋刃拵)

This traditional-style koshirae combines practical function with traditional design. The saya has a glossy crimson lacquer finish. The koiguchi, kurigata, and kojiri are reinforced with water buffalo horn for durability. The sageo is tied in a standard pattern. The tsuka is wrapped in black ito with hishigami inserts for a tight, symmetrical grip. Beneath the wrap is a layer of natural ray skin. The menuki are made of blackened and polished white copper, depicting a dragon coiled around a sword. The fuchi-kashira, also in white copper with a wave motif, are treated with a blackened polish and paired with a kuruma-sukashi tsuba in blackened iron.

---

TangGu (湯谷) Maru Blade

This blade is hand-forged (Tezukuri / 手作り) using high-performance modern steel (現代鋼), with a monosteel construction known as Maru-zukuri（丸造）.

Blade Forging Details

• Blade Name: TangGu Traditionally Forged Maru Blade (丸造)
• Forging Method: This blade is forged in the Maru-zukuri style, using a single piece of modern high-performance steel, and fully heat-treated (全体焼入れ) throughout the entire blade for uniform hardness and durability.
• Materials: Modern high-performance steel (現代鋼)
• 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 71 cm
• Handle Length (Tsuka 柄長): Approx. 24 cm
• Width at Base (Motohaba 元幅): Approx. 32 mm
• Thickness at Base (Motokasane 元重): Approx. 6 mm
• Width at Tip (Sakihaba 先幅): Approx. 24 mm
• Thickness at Tip (Sakikasane先重): Approx. 4 mm
• Kissaki Length (Tip 切先長): Approx. 35 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 (Modern monosteel; no visible hada)
• Temper Line (Hamon 刃文): None (Fully quenched blade; not differentially hardened)

Special Features and Workmanship

Hi (Groove) Engraving

• Type: Shinken Hi (真剣樋) with Marutome Tome (丸留め止め).
• Processing Range: Extends to the tip, fully polished inside the groove

Polishing Work

• TangGu Polishing Levels:
  • Standard Polish
  • Mirror Polish

Fittings and Mountings

Blade Fittings

• Tsuba (Handguard 鍔): Kuruma-sukashi Tsuba – Blackened Iron (鉄地)  Wheel-style Guard (Practical Use)
• Fuchi-Kashira (縁頭): Wave-patterned Fuchi-Kashira – Blackened & Polished White Copper
• Menuki (目貫): White Copper Menuki – Dragon Wrapped Around Sword (Blackened & Polished).
• Habaki (鎺): Crafted from white copper (shiragane / 白銅) with a smooth – finish.
• Samegawa (Ray Skin 柄鮫): Premium natural ray skin
• Handle Wrapping (Tsuka-maki 柄巻): High-quality black silk (or cotton) tsuka-ito, wrapped with hishigami (paper triangles)

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): Glossy bright red lacquer
• Sageo (Cord 下緒): High-quality black rayon sageo, offering a secure and characterful presentation.

Measurements

• Blade Weight: Approx. 0.6 kg
• Sword Weight (without Saya): Approx. 0.95 kg
• Total Weight: Approx. 1.2 kg
• Overall Length: Approx. 102 mm