Cufflinks

1900?  Cufflinks of a tortoise whose shell opens to reveal a hare.  Made in England?  Hallmarket Silver?  Source unknown.

This is some of the most delicate small work in the collection!  Each cufflink has a hinged tortoise back.  Opening it with clumsy fingers is not easy!  Does the Hallmarket Silver box belong to this exquisite pair?  And what brings a person to wear openable tortoise-and-hare cufflinks?  Matched tortoise cuffliniks seem common enough on the web.  I have not yet found TH cufflinks.