Vintage interchangeable locket Aventurine cabachon 925 sterling silver pendant

Vintage locket ots sterling 925 stamped very neat piece, it has a natural aventurine cabachon stone in it right now but you can change that out and put any cabachon you want in it as long as it's the same size, This looks to be Asian inspired design, see all photos, excellent condition just needs polished. The first photo is of the back but you can wear it either way if you like. measures right over 1" tall. Box 15