This item in the Urban_Archaeology Collection ticks all our interest boxes. Our research has shown the same piece sold in the UK, twice previously. 1) and 2) - Maker: Patrick Robertson. Edinburgh c1790.
A rare Georgian Scottish silver Helter Skelter Club Badge of plain oval form with tied ribbon and ring surmount, the face engraved with a crest of a heart with an arrow through it below the motto ‘Thus Far’. To Robt Campbell Original Member. The reverse with the instituted date 8th May 1790 and the initials D.W.B.C.
Further research on the Helter Skelter Club is supplied by Michael Allen:
Sir Walter Scott: St Ronan’s Well (written c1823)