Antique silver salt hallmarks and country id help please

Hi this silver salt was found in bits , some on which were outside amongst rubbish . The only marks are a makers mark FC and the number 6 .The top salt cellars and base are made from plate sinlev while the dolphins are hollow cast . Hope the pics are ok but if not please email . We have been told that this could be a very early ( 1600s) piece of silver . I have a small collection of silver and love Channel Islands wedding spoons . thanks Justin :smiley:
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