Vintage Tie Pin with Green Onyx or Marble Inset (SOLD)

This tietack consists of a green speckled natural stone square( probably Onyx or marble, it may even be the Irish Connemarra Marble) set in a goldtone metal. Easy to use this simply pins through the tie into a twist back guard.  There is a chain and bar attached to this to enable the tie tack to be further secured through a button hole.  I would estimate that this vintage accessory dates from the 1970s or 1980s eras.