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Myojin Riki  |  SKU: MJ-COSP-BU180

Myojin Cobalt Special COSP Bunka 180 mm

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K&S Price: AU $349.95* inc. tax , vs:
Chefs' Edge AU $359.0 -2.87%
Knifewear AU $463.0 -32.66%

* For overseas buyers you pay no GST (10%) and low shipping rate.
Last Update: 2024-04-16T01:00:50Z

Detailed Specifications
Line Myojin Cobalt Special COSP
Profile Bunka
Bevel Type Double Bevel
Weight 131 g        4.62 oz
Edge Length 169 mm   .6.65 inch
Heel Height 48 mm     .1.89 inch
Width @ Spine 2.1 mm     0.08 inch
Width @ Mid 1.9 mm     0.07 inch
Width @ 1cm from Tip 0.8 mm     0.03 inch
Steel COSP (Cobalt Special) | Stainless
Blade Construction Sanmai - Stainless Clad
Hardness (HRC) 59 - 60
Surface Finish Migaki
Handle Octagonal Teak Black Ferrule
Region Tosa
Best for
  • First-timers
  • Pro chefs
    • Free shipping for knives over AU$200 Australia wide.
    • World-wide shipping via DHL Express, 3 to 5 days.

    The Cobalt Special (COSP) knives from Myojin Riki feature blades crafted from Cobalt Special steel, a high-end Japanese stainless steel known for superior edge retention, sharpness, and corrosion resistance. Enriched with carbon and chromium, it offers excellent durability. The addition of cobalt, molybdenum, and vanadium enhances its hardness, making it ideal for everyday use.

    Pros Cons
  • Easy to look after
  • Excellent fit and finish
  • Thin behind the edge
  • More sharpening needed

  • Care Instruction
    1. Don't cut hard things! Japanese knives are brittle so bone hacking is a NO NO!
    2. Wash with netural detergent after use, and wipe dry;
    3. Please don't wash knife with dishwasher, it will damage the wood handle;
    4. Be careful not to leave the knife close to a heat source for a long time;
    5. It is a lot more dangerous to cut with a blunt knife than a sharp knife!
    6. It is best to sharpen a Japanese knife regularly on a waterstone.

    Myojin Riki

    The Myojin Riki Manufacturing, established by a founder who mastered his skills in Osaka, the heartland of blade-making, has been operational for over 80 years. Specializing in knives made from steel and iron, they've recently focused on stainless steel knives, valued for their light weight, resistance to rust, and exceptional sharpness. These knives are popular among both professionals and general consumers, partly due to their application of the "stacked steel pattern" traditionally found in swords. The second generation continues to innovate, customizing products to meet users' needs, while also contributing to cultural preservation through their involvement with local traditional performances and blade repairs.

    • Profile: Bunka

      A pointier version of the Santoku. The Bunka knife features a distinctive profile with a straighter edge and a pointed tip, making it versatile for a variety of kitchen tasks. Its design is a blend of the Santoku and Gyuto knives, with a blade length typically around 165mm to 180mm. The Bunka is particularly adept at slicing, dicing, and chopping fruits, vegetables, and meats, thanks to its sharp edge and comfortable handling. The angled tip, also known as a reverse tanto, provides additional precision for intricate tasks such as julienning. With its unique shape and functionality, the Bunka stands out as a multifunctional knife in the culinary world.

      Slide for more >>

    • Steel: COSP (Cobalt Special)

      Takefu Special Steel's Cobalt Special steel, often referred to as Cobalt Steel, is a premium high-performance steel known for its exceptional edge retention and hardness. This steel incorporates a significant amount of cobalt in its composition, enhancing its wear resistance and strength. The addition of cobalt, along with other elements like carbon, chromium, and molybdenum, allows the steel to achieve a high level of hardness without compromising its toughness. Cobalt Special steel is designed to maintain a sharp edge for extended periods, even under rigorous use, making it highly valued for crafting high-end kitchen knives and cutting tools.
      Makers such as Mojin and Kurosaki have some excellent COSP offerings.


      • Takefu Special Steel, Japan

      Nature: Stainless

      Hardness: 59- 60

      << Slide for more >>

    • Construction: Sanmai - Stainless Clad

      Sanmai(Three-Piece) is a common construction for double bevel knives where two pieces of softer cladding steel are forgewelded to each side of a harder core steel. The harder but more brittle core steel will form the hard cutting edge after heat treating, and the softer cladding will support the core to increase the overall strength of the blade.

      The soft cladding enables the thinning process to be a lot easier than a honyaki or monosteel construction. And in the case where the cladding steel are stainless in nature, it can offer protection for the carbon or semi-stainless cores against rusting and discoluoring.

      << Slide for more >>

    • Finish: Migaki

      "Migaki" means "polished" or "shined" in Japanese, The term "Migaki finish" in the context of Japanese kitchen knives indeed does not exclusively refer to a mirror polish but encompasses a broader range of polished finishes that can vary from semi-gloss to a more refined, subtle sheen, rather than a highly reflective surface. The primary goal of a Migaki finish is to enhance the knife's functionality and aesthetic appeal, focusing on a smooth finish that improves resistance to corrosion and minimizes drag during cutting, rather than achieving a purely mirror-like appearance.

      << Slide for more >>

    • Handle Specs

      Profile: Octagonal WA


      • Teak
      • Black Buffalo Horn

      The teak wood, known for its durability and rich grain patterns, provides a sturdy yet comfortable grip for precise handling during culinary tasks. Complemented by the sleek black horn ferrule, the handle boasts a striking contrast that adds sophistication to the overall design.

      Fashioned in an octagonal shape, the handle offers ergonomic benefits, allowing for a secure and comfortable grip from various angles. Its tapered design from bottom to top ensures a balanced feel and optimal control, promoting effortless maneuverability while slicing, chopping, or dicing ingredients.

      << Slide for more

    Myojin Riki

    Myojin Cobalt Special COSP Bunka 180 mm



    Weight 131 g
    Tip to Heel Length 169 mm
    Blade Height at Heel 48 mm
    Width of Spine Above Heel 2.1 mm
    Width of Spine at Middle of Blade 1.9 mm
    Width of Spine at about 1 cm from tip 0.8 mm


    Steel type: Cobalt Special core with stainless clad

    Hardness (HRC): 60 - 61

    Handle Design: K&S Teak wood handle. Optional handles available.  

    Another quality offering from Myojin. The Cobalt Special Steel line is practically idential to the more expensive SG2 line: same grind, same profile, and the equally excellent performance. The Cobalt Special steel from Takeful Special Steel is an excellent alternative to the state-of-the-art VG10 steel, offering great wear resistance and edge retention. 


    Naohito Myojin (明神 直人) is a young sharpener based in Kochi prefecture. While his workshop Myojin Riki Seisakusho is probably not as famous as the established brands from Sakai and Echizen, he is the sharpener behind some of the very famous knife lines in the industry; noteabley the Tetsujin brand and the 'Fujiyama' line by Konosuke. 

    Naohito Myojin Sharpening

    I think 'refined' is the best word to describe Naohito's work: while featuring proven cutting performance, his knife has some of the best finishes out there. The spine is nicely chamfered, choil is well polished. By engraving his name Naohito on to the knivves, you can tell that he must be really proud of his work, and I trust you will enjoy his knife as well. 

    Naohito Myojin Portrait

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