Large Art Deco, Machine Age Silver, Onyx & Gemstone Earrings

These Art Deco earrings are big at 2in high x 1in wide. My wife tells me they sit very comfortably because the old style spring clips hold them securely while they hang from the pierced ear posts.

They are onyx and sterling silver, stamped 925. The previous owner said they dated to the 1930's and the gems tested as peridot, amethyst, citrine, blue topaz, and garnet, although I haven't had them checked yet.

They remind me of Gerard Sandoz, Jean Després, Raymond Templier etc pieces and I feel like I've seen the design before, but maybe that is just because they are so typically Deco. To me they have a Machine Age / USA feel to them.

Any suggestions as to maker, period, or country of origin?