The major parts of a Rondel dagger

The major parts of a Rondel dagger, tapering single edged blade 14 in., the back reinforced with a diamond section rib; iron guard formed of two round plates united by a plain band, rectangular tang pierced with three large rivet holes, brass or gilt metal back strap with broad diagonal flutes; lacks grip, pommel and scabbard, possibly 15th-16th Century.