Calligraphy Brooch or Pen Pin

Offering a vintage calligraphy pen brooch or pen pin. The handle is mother of pearl with a gold filled metal pressed in design leading to the nib. The pin slides up & down on the MOP handle for ease of attaching. There is stamped in lettering at each end of the pressed design, the nib end is JOHN, I can't make out the handel end using a loupe in the sunshine. A prefect gift for the writer. Measures just shy of 6" long