These are lovely and petite Abalone Shell Post earrings. I made the Sterling Silver Backs. The abalone shell measures approximately 5x7mm.
I generally get my stone materials and cut, shape and polish them myself. I procure the gold or silver metal flat or as rolled wire or tubes and use it to shape and create my designs.
Hand-crafted art/jewelry are one-of-a-kind pieces and generally are not duplicated exactly. Stones vary, measurements vary. I can collaborate with you if you would like to have a piece made for you or for someone else. Sterling silver may be polished with any number of good silver cleaner/polish products. Natural stones are fragile and may break if dropped, heated directly, stepped on, etc. Care should be taken.