Silver maker on thimble: JC

Any idea of the age of this thimble,please? It has a maker’s mark of JC (above the initials) but no hallmarks so I guess it is old. It has a slit down the side to expand it…I found a James I coin near it. Thanks.Richard

Just to inform you that the British Museum has declared this treasure, being over 300 years old and made from silver. Thanks for trying to ID