Japanese ring counters use many words that are hard to look up: kōmaru, hirauchi, miru-uchi and more. Knowing them helps you follow the staff's explanation and describe what you like in a few words, such as "a slightly thinner kōmaru with a matte finish". The terms are grouped into shape, surface, production method, metal and stone setting.

1. Shape (profile and line)

  • Kōmaru (甲丸): a band with a rounded, domed profile. The most classic shape for Japanese wedding rings, gentle on the finger.
  • Hirauchi (平打ち): a flat profile with crisp edges. Strong presence, popular with men.
  • Uchi-kōmaru (内甲丸): "comfort fit" — the inside of the band is rounded so the ring slides on easily and feels comfortable all day.
  • Straight / wave / V-line: the line of the ring seen from the front. Wave and V shapes are said to make fingers look longer.
  • Width and thickness: roughly 2–3 mm counts as slim and 3.5 mm or more as wide. Width changes the look of a design a great deal.

2. Surface finish

  • Kyōmen (鏡面) / polished: mirror-polished.
  • Tsuya-keshi / matte / hairline: finishes with reduced shine. Hairline means fine parallel lines brushed in one direction.
  • Miru-uchi (ミル打ち) / milgrain: a row of tiny beads along the edge. Classic, often used on antique-style rings.
  • Tsuchime (槌目): a hammered texture whose expression changes with the light.
  • Combi (コンビ): two metals combined in one ring, such as platinum and gold.

You can see the rings in person at a store near you.Find a store near you

3. Production method

  • Tanzō (鍛造) / forging: the metal is hammered or pressed into shape. Dense, and considered resistant to bending and scratches.
  • Chūzō (鋳造) / casting: molten metal is poured into a mould. Good for reproducing delicate designs. See forging vs casting.
  • Juchū seisan (受注生産) / made to order: the ring is made after you order, in your size, metal and engraving. This is the norm for Japanese bridal rings; allow several weeks to a month or more.

4. Metals

  • Pt900 / Pt950: 90% / 95% platinum. Pt900 is the most common choice for bridal rings in Japan.
  • K18: 18-karat gold (75% gold), in YG (yellow), PG (pink) and WG (white).
  • K10: 10-karat gold (41.7% gold), used in more affordable lines.
  • Hard platinum: platinum alloyed for extra hardness, so even slim rings resist bending. See the metal guide.

5. Diamonds and settings

  • Melee (メレ): small diamonds under about 0.1 ct set along the band. "Mere-nashi" means a plain ring without them.
  • Tsume-dome (爪留め) / prong setting: the classic engagement-ring setting with claws holding the stone.
  • Fusekomi (伏せ込み) / flush or bezel setting: the stone sits down in the metal, so it does not catch and suits daily wear.
  • Eternity / half eternity: diamonds all the way round, or halfway round, the band.
  • Secret stone: a small stone set inside the band, often a birthstone. See what is a secret stone.

6. Buying

  • Gō (号): the Japanese size unit. For conversions see the ring size conversion chart.
  • Kokuin (刻印) / engraving: lettering inside the band; dates and initials are the classic choice. See engraving ideas.
  • Set ring: an engagement ring and wedding ring designed to be stacked together.
  • After-sales service: resizing, re-polishing and checking stones. Coverage and free periods vary by brand.

Once you know the name of what you like, compare real rings in the wedding ring list and engagement ring list. The visit itself is covered in our guide for overseas visitors.