Anyone recognise this medallion

[roycymru]

Not sure if this the best place to post this. I recently colourised a picture of my great grandfather John Davies. Colourising it made a "medallion" he was wearing stand out, something I had never appreciated before. Does anyone have any idea what the medallion relates to?

John was born 1869 and at a guess the attached picture was taken around 1910 onward. He was a collier, lived in Pontyberem, was a talented cricketer, tennis player and carpenter, all or none of which may have any bearing on the photo.

Thank you