Vintage 925 sterling silver ring w natural marcasite stones and crystals

Vintage sterling silver Maximalist statement ring. With natural marcasite stones and clear crystal stones. Size 7. Stamped 925 R and China on the inside, so I assume that it is made of solid sterling silver (but never tested it, so can't guarantee it). One crystal stone on the very end is missing, as shown in the closeup picture. But because of it's design, this area is always hidden when the ring is being worn.