This may have been Henry VIII's personal dagger from the early 16thC. The original dagger features a 1960's grip replacement whilst mine shows what might have been..... Delicate shell guard and strong hollow ground blade. Cap is speculative as original is missing.
Example shows a custom steel throat fitting but comes with a leather sheath and bronze chape.
Single edged with a 32cm blade
Specification
Grip length – 10cm
Blade length – 32cm
Overall length – 46cm
Blade thickness at hilt – 7mm
Handle components – Steel