Vintage Silver Metal Post Lever-back Earrings

Vintage Silver Metal Earrings. Not sure what type of metal, but they shined up beautifully with a polish cloth. They are lightweight hollow, swirl-oval-dome shaped. Design is BOTH post and lever-back so they are very secure! Length is 7/8". These earrings are unique, pretty, and in great condition! I am not sure what decade they are from, but at least back to the 70s based on the source. Photographed outdoors, so they are reflecting their surroundings somewhat.