Vintage 1930s Czech Glass Blue Beads Hand Strung on Brass Round Brooch Pin Trombone Clasp

Circa 1930s brooch/pin, composed of blue Czech glass beads hand strung onto silk and adhered to brass.
Back of brooch has a trombone clasp. The trombone clasp was first seen in use in the early 1890s on European jewellery. Many brooches made in France displayed this type of clasp and they were commonly used in jewelry made in up until the 1940s.

Brooch measures approximately 1.5 inches in diameter.
In great condition for its age. Please see all photos.