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Mujimono

By the koi.wiki editorial team · Updated

Key facts: Mujimono (無地) is the variety classification for non-metallic koi with a single, even body color and no pattern, encompassing fish such as Chagoi, Soragoi, Benigoi, Kigoi, Karasugoi and Karashigoi.[1][2]
Colors:
  • cha (brown)
  • sora (gray-blue)
  • hi (red)
  • ki (yellow)
  • sumi (black)
Screen colors are approximate and only a visual aid.
Mujimono (無地), often shortened to muji, is the Zen Nippon Airinkai (ZNA) and All Japan Nishikigoi Promotion Association (JNPA) classification used for single-colored, non-metallic koi that show no imprint pattern across the body.[1][2] The Japanese Agricultural Standard (JAS) for nishikigoi vocabulary defines the variety muji (無地) simply as a koi “with no imprint,” numbered entry 2022 in the standard.[3]Because the category is defined by the absence of pattern rather than by a specific color, it covers a wide range of ground colors, from the brown Chagoi and gray-blue Soragoi to the bright red Aka-muji (also called Benigoi), the yellow Kigoi, the jet-black Karasugoi and the large yellow-bodied Karashigoi.[2][1]

Name and classification

Mujimono groups together koi that are a single, even color with no contrasting pattern.[1] According to the All Japan Nishikigoi Promotion Association, “Muji is a general name for single-color Nishikigoi that have no patterns on their bodies.”[2] The term muji appears in judging glossaries as meaning “self-colored,” literally “nothing else.”[7]Mujimono is distinct from Hikari-mujimono, which is the equivalent classification for single-colored metallic koi such as Ogon and Platinum Ogon; the American Koi Judges Association glossary lists Hikari Mujimono separately as “the classification for single-colored metallic Koi.”[7]

Judging points

  • Evenly colored skin all the way to the tips of the pectoral fins is highly valued.[2]
  • Good body shape is valued alongside even coloration.[2]
  • The defining standard criterion is absence of any imprint pattern across the body.[3]
  • Large Karashigoi, sometimes exceeding one meter, are noted for remarkable show performance.[2]
  • Doitsu and Ginrin muji are judged within the Mujimono class rather than separately.[1]

Appearance and the JAS standard

The Japanese Agricultural Standard for nishikigoi vocabulary (JAS 0020) defines muji (無地), entry number 2022, as a koi variety that simply “has no imprint” (斑紋がないもの).[3] The same standard notes that a single individual can show the appearance characteristics of more than one defined variety, and which variety name is applied is left to the user of the standard — for example, a fish combining the characteristics of Kujaku and Doitsugoi may be classified as either.[3]The JNPA states that in the Muji category, koi that are evenly colored all the way to the tips of the pectoral fins and that have a good body shape are highly valued.[2]
Photograph of a Chagoi koi
Chagoi koi. Photo: KoiQuestion, CC BY-SA 2.0, via Flickr (via Openverse).

Sub-types within Mujimono

Scale forms: Doitsu and Ginrin Mujimono

Mujimono koi can occur in scaled, Doitsu (scaleless or partially scaled, German-derived) and Ginrin (sparkling-scale) forms. ZNA states that Doitsu Muji and Ginrin Muji should be entered in the Mujimono class at ZNA koi shows.[1]The JNPA lists several named Doitsu muji combinations, including Doitsu-aka-muji, Doitsu-shiro-muji, Doitsu-kigoi, Doitsu-chagoi and Doitsu-karashigoi, each described as having almost no scales with the skin exposed, combined with the body-color characteristics of the corresponding muji variety.[5]Similarly, the JNPA lists Ginrin-aka-muji, Ginrin-shiro-muji, Ginrin-kigoi, Ginrin-chagoi, Ginrin-soragoi, Ginrin-karashigoi, Ginrin-aka-matsuba and Ginrin-ki-matsuba, each combining shining golden or silver scales with the appearance of the base muji variety.[6] See also Doitsugoi (Doitsu koi) and Kinginrin (Ginrin).

Classification at shows

At ZNA shows following the 2021 ZNA classification, Mujimono is class 15 and groups together Chagoi, Soragoi, Karashi(goi), Matsuba, Ginrin Muji, Karasugoi, Kigoi, Midori Goi, Aka Muji, and the Doitsu and Ginrin muji combinations.[4] This sits alongside, but separately from, class 16, Hikari Mujimono, which covers metallic single-colored koi such as Ogon, Platinum Ogon and Yamabuki.[4]Under the JAS vocabulary standard, muji is entry 2022, defined purely by the absence of imprint pattern, independent of the show-category subdivisions used by ZNA or the JNPA.[3]

How Mujimono differs from similar classes

Mujimono is defined by having no pattern at all, which distinguishes it from Kawarimono, a broad non-metallic class for koi that do not fit other named varieties and that typically do show irregular markings — for example, black or white bodies with markings of various colors, according to the US importer Kodama Koi Farm.[8]Mujimono is also distinct from Hikari-mujimono, the metallic single-color class covering varieties such as Yamabuki Ogon and Platinum Ogon; both share the “single color, no pattern” rule but differ in whether the scales are metallic.[7][4]

Judging notes

In the Muji category, the JNPA states that koi which are evenly colored all the way to the tips of the pectoral fins, and which have a good body shape, are highly valued.[2] The JNPA also notes that Karashigoi, which can grow larger in size, often exceeding one meter in length, give a remarkable performance at koi shows.[2]
Photograph of a Chagoi koi
Chagoi koi. Photo: KoiQuestion, CC BY-SA 2.0, via Flickr (via Openverse).
Schematic diagram of the colors used in Mujimono
Schematic color diagram for Mujimono, drawn by koi.wiki. It shows the colors named in the sources, not a real fish or an ideal pattern.

Entries in this section

Common questions

What does Mujimono mean?
Mujimono (無地) is the classification for non-metallic koi with a single, even body color and no pattern, as used by the Zen Nippon Airinkai and the All Japan Nishikigoi Promotion Association.[1][2]
What varieties are included in Mujimono?
Mujimono includes Chagoi, Soragoi, Benigoi (Aka-muji), Kigoi, Karasugoi, Karashigoi, and matsuba-patterned muji such as Aka-matsuba and Ki-matsuba.[1][2]
How does the JAS standard define muji?
JAS 0020 defines muji (entry 2022) simply as a koi variety with no imprint (斑紋がないもの) on the body.[3]
Are there Doitsu and Ginrin versions of Mujimono koi?
Yes; ZNA rules state that Doitsu Muji and Ginrin Muji should be entered in the Mujimono class, and the JNPA lists specific forms such as Doitsu-chagoi and Ginrin-kigoi.[1][5][6]
How is Mujimono different from Hikari-mujimono?
Mujimono covers non-metallic single-colored koi, while Hikari-mujimono is the separate classification for single-colored metallic koi such as Ogon and Platinum Ogon.[1][7][4]

References

  1. ^ MUJIMONO | Zen Nippon Airinkai. Zen Nippon Airinkai. zna.jp/en/keep-nishikigoi/varieties-of-nishikigoi/mujimono/. Retrieved November 2026.
  2. ^ Muji - Variety - All Japan Nishikigoi Promotion Association. All Japan Nishikigoi Promotion Association. jnpa.info/en/nishikigoi/varieties/type/muji/. Retrieved November 2026.
  3. ^ JAS 0020 Nishikigoi. Vocabulary (MAFF) — Ministry of Agriculture, Forestry and Fisheries (Japan). maff.go.jp/j/jas/jas_standard/attach/pdf/index-536.pdf. Retrieved November 2026.
  4. ^ Koi classification (ZNA 2021), NMZNA 2026 show documents. nmzna.net. nmzna.net/2026%20Show%20Docs/NMZNA%202026%20Koi%20Classification%20…. Retrieved November 2026.
  5. ^ Doitsugoi - Variety - All Japan Nishikigoi Promotion Association. All Japan Nishikigoi Promotion Association. jnpa.info/en/nishikigoi/varieties/type/doitsugoi/. Retrieved November 2026.
  6. ^ B-ginrin - Variety - All Japan Nishikigoi Promotion Association. All Japan Nishikigoi Promotion Association. jnpa.info/en/nishikigoi/varieties/type/b-ginrin/. Retrieved November 2026.
  7. ^ Glossary – American Koi Judges Association (AKJA). American Koi Judges Association. akjajudges.com/glossary/. Retrieved November 2026.
  8. ^ Kawarimono Archives - Kodama Koi Farm. Kodama Koi Farm (koi dealer). kodamakoifarm.com/variety/kawarimono/. Retrieved November 2026.