Scarf or Tie Bar Clasp Large Faux Turquoise Stone

Not quite sure what this beautiful stone is, but believe it is glass. Truly a lovely piece, set in gold-tone metal, and with an interest "clasp" at the back which makes it work well for scarves around the neck, or ties, and will hold them gathered quite well. Cabachon decoratin is 7/8" diameter, entire piece is 1-5/8" side-to-side. Excellent condition with some cleanable oxidation to the metal. Unmarked, age and origin unknown. Vintage. $4.75 US First Class Shipping.