COIN (ROMAN)
A Cu alloy coin possibly of late Republican date. 

It is very worn and was found with lots of 4th century nummi so perhaps it has been kept as a good luck charm which would explain its presence with coins of a later date.
Denomination: Uncertain
Material: Copper alloy
Obverse: Bust facing left wearing helmet.
Obverse legend: Illegible.
Reverse: Illegible.
Reverse legend: Illegible.
Weight (g): 1.5
Diameter (mm): 15.57
Thickness (mm): 1.74
Completeness: Complete
District: Kettering
County: Northamptonshire
Region: East Midlands
Discovery method: Metal detector
Notes: Left facing helmeted busts are quite common in the period AD 317-330.  Without a photograph it is not possible to comment further, but it does not seem to be Republican (Sam Moorhead)