Like, oh, say, an engraved gold ring with a black diamond given by Edward III to a Flemish supporter in the 14th century.

After a bit of spit and polish, it was clear that this was no ordinary ring. It was certainly gold and crowned with a black diamond. It also carried the inscription “loyaute sans fin”, French for “loyalty without end”.

Elsewhere, it appeared to carry the letter “E” three times, each one followed by three stars. And either side of the “bezel” – the diamond centrepiece – sat two gold initials: “V” and “A”.

Read the whole swashbuckling tale here.