RARE Green “Jade” German Glass Brass Bracelet Vintage or Antique

The bracelet is a vintage or antique piece, likely from the Art Deco period of the 1920s to 1940s, or later from the mid-century period. Signed Germany - it looks/feels like German glass, but could be another material. There is some brass fading in places- see photos for details. Working, original spring clasp. Brass over unknown metal.