See our: buckle jewelry.
A buckle (always in pair) attached to a man's or woman's shoe, of two types:
The ordinary form of buckle through which a pierced strap passes and is secured by a pointed tongue The buckle that is attached by prongs or sewing to the top of the vamp of the shoe, not as a fastener but only as a decoration.
The shape of the latter type is usually oval or rectangular, and examples have been decorated in a multitude of styles, with ornaments often of marcasite, cut steel, jet, paste, or, for luxury shoes in former days or the present, gemstones. The 18th-century shoe buckles ceased to be used as fasteners when shoe-strings were introduced. Modern shoe buckles are sometimes used decoratively at the side of the vamp. The Lady Maufe Collection of about 1300 18th- century shoe buckles is at Kenwood House, London.
From: An Illustrated Dictionary of Jewelry, autor: Harold Newman, publishers: Thames and Hudson