Antique brass bar collar pin 1920’s or before

A very old, functional pin like those worn in the late 1800’s to the 1920’s. I know the provenance of this particular item. It was worn by either Mabel or Allie Reed, both of whom were maiden schoolteachers from a micro town in southwestern Pennsylvania, Rea Station in Cross Creek Twp, Washington County, PA. See pic of their house, which I grew up in. Last pic is an example of how these bar pins were worn.