In the sub-category of swords, in many cases, only the blade of the tachi (long sword), tanto (dagger) or other swords are made a national treasure, while in the case of kazari-tachi (decorative swords), most often it is the exterior bodywork (the hilt, etc.), not the blade, that is named a national treasure.
刀剣は太刀、短刀などの刀身のみ指定されているものと、飾剣（かざりたち）のようにおもに外装が指定対象になっているものとがある。