Inlaid Sterling outlet Heart and Feather Dangle Earrings

outlet Pretty vintage sterling heart earrings, with an inlay inset of spiny oyster, turquoise, sugarlite, malachite, onyx, coral, and lapis. Each earring features 2 sterling feathers that dangle down.
Marked "(M) 925" I have not been able to ID the maker.

Condition is excellent. There are no dents or dings. No chips or cracks. Ready to wear.