Hand of Glory
It is possible that someone plucked an old love from the grave to send you this. More likely they bought it at Hangman's Arch. Possibly it means they value you more than their own right hand. It's hard to be certain.
An admirer might send you this at the Feast of the Exceptional Rose.
See here for
It cannot be bought or sold at The Echo Bazaar!.
Effects when equipped in Gloves slot:
See here for , or click to show them.