The link below reports about the discovery of Merovingian gold coins in Norfolk, England https://www.bbc.com/news/uk-england-norfolk-59151380
Dirk, Thanks for posting this article . The top photo looks Merovingian, but the other side of the coin isn't posted . The other photos look like a Justinian I solidus from the Constantinople mint.
I'm not sure, but I don't think that obverse and reverse above are from the same coin. The obverse shows an imitative Frankish tremissis (boucle perdue- type), dated to around 580s. The reverse seems to be Byzantine solidus.
Other coins from this hoard can be seen in this interesting essay by Adrian Marsden, see the link below . https://www.academia.edu/50825390/Norfolk_Archaeology_2020_Adrian_Marsden
Huge thanks to both of you for the fantastic links! ...I look at the BBC every day, and I always miss this stuff.