At first sight this find looks like an early Anglo-Saxon cut halfpenny. Tom Burton believed it to be a coin of Offa but said he wasn’t 100% certain.
Firstly this is too small to be a cut farthing, as it will be only one third of a penny. On the obverse is REX and above this, on a whole penny, would be two more lines. The top two lines would be two sections of the name of the ruler for whom it was struck. Or, for a king with a short name (Offa, for instance), the middle line would be the king’s name, the bottom line REX and the top line often a single Anglo-Saxon style letter M.
If the curve is at the top then on the reverse of Tom’s find is an Anglo-Saxon M with a bar across the centre and a trefoil of pellets either side. Therefore, the obverse would originally have been the bottom of a whole penny and the reverse would be the top.
This find does look like the three-line type of Offa of Mercia, so I thought it would be fairly easy to pin down in my copy of The Coinage of Offa and His Contemporaries. However, after checking through all the 258 types I could not trace a specimen with an obverse and reverse that matched Tom’s find. Other issuing authorities contemporary with Offa also issued pennies bearing similar designs, so I had to widen my research.
I eventually traced a coin of Eadberht Praen (King of Kent, 796-98), which had at the top of the reverse a design very similar to that on Tom’s find. It wasn’t an exact match but was in my opinion near enough for me to say that rather than being a coin of Offa, Tom’s find will have been struck for Eadberht Praen.
Detectorists have unearthed lots of coins of Offa but most of the known types are still very rare. However, Eadberht Praen had only a very short reign and his coins are much rarer.
This find isn’t a cut halfpenny. Instead it is roughly one third of a penny. Therefore, it would be worth less in cash terms than a cut halfpenny. As I’ve said a number of times, cut halfpennies sell for much lower figures than whole pennies. On the plus side, this find is what remains of a penny struck for Eadberht Praen, whose coins are extremely rare. Despite the fact that some would regard it as only a fragment, a collector on a budget might be willing to pay around £150 for it.