Katana Golden Mist Maru Blade Kinkasumi Koshirae 當康

Clay Tempered Full Tang Shinken (真剣) | Golden Mist Katana: TangGu (湯谷) Maru Blade (丸造) + TangGu (湯谷) Hantachi Kinkasumi Koshirae (金霞拵)

The sword is mounted in a Hantachi-style koshirae (半太刀拵). The blade is hand-forged in Maru-zukuri (丸造) style from proprietary high-carbon steel for structural consistency and edge retention. It has no visible hada (鍛肌なし). A straight Suguha hamon（直刃刃文）is formed through clay tempering (覆土焼入れ). The saya (鞘) features raden-style lacquer (螺鈿塗)—a glossy black surface with fine reflective particles. Koiguchi and kurigata are buffalo horn; kojiri is metal reinforced. Yellow cotton sageo (下緒), tightly woven. The tsuka (柄) is wrapped in yellow cotton ito over aged ray skin (鮫皮), reinforced with hishigami (菱紙). Brass menuki (目貫) feature kamon (家紋) motifs. Fuchi and kashira (縁頭) are steel with a smooth, undecorated surface. The tsuba (鍔) is a mokko-gata (木瓜形) made of antique-finished brass.

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: Designed for Iaido (non-sharpened), Kenjutsu, and Tameshigiri (test cutting) practice, as well as for collection, display, and appreciation by enthusiasts and connoisseurs.

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 a uniform grain.
• Hamono (Blade Pattern 刃文): Suguha（直刃） — Straight hamon formed by clay tempering (覆土焼入れ).
  

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 straight Suguha（直刃）hamon with a brightened edge (Hashiro / 刃白). 

Fittings and Mountings

Blade Fittings

• Tsuba (Handguard 鍔): Mokko-gata (木瓜鍔) made of brass with an aged finish. Plain surface.
• Fuchi-Kashira (縁頭): Steel with smooth, undecorated surface.
• Menuki (目貫): Brass menuki with kamon (家紋) motifs.
• Habaki (鎺): Hand-forged from brass with an aged, antique finish.
• Samegawa (Ray Skin 柄鮫): Natural ray skin aged to a soft yellow hue.
• Handle Wrapping (Tsuka-maki 柄巻): Yellow cotton ito, tightly wrapped.

Saya and Accessories

• Saya (Scabbard 鞘): Hantai-tachi (半太刀拵) style. Koiguchi and kurigata made of buffalo horn; kojiri reinforced with metal.
• Saya Lacquer (鞘塗): Raden-style (螺鈿塗) lacquer with glossy black base and fine reflective particles.
• 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. 1.4 kg
• Overall Length: Approx. 100 mm