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Obidome (帯留め, おびどめ) are small brooches worn threaded onto the obijime, making a charming decoration on the front of the obi. Can be made of wood, ceramic, resin, mother-of-pearl, or precious metals. Often in designs such as flowers, small objects, or animals.
The back surface will almost always be flat with two closely-spaced raised rectangular holes, used for sliding the obidome over the thin flat obijime cord.
When an obijime is made specifically to be worn with obidome, it will be thinner and flatter than average, and known as sanbu-himo.
These are generally the only jewelry that is acceptable to wear with kimono (other than a wedding band or tasteful watch). Typically an informal item, even when made with precious gems and are only acceptable with more casual or funky outfits.
However, Maiko will wear a very large and elaborate form of obidome known as pocchiri with their hikizuri. These are often made of incredibly fine materials such as gold and diamonds or emeralds, as well as very detailed enamel workmanship. They are also much larger than normal obidome.