This large ring of cast and applied silver is from Yemen. It comprises a hoop variously decorated with applied plaques and granulation work. The bezel comprises a tall, hollow dome constructed from silver wire in a basket-like format and decorated at the top with a tall heap of silver spheres.
See van Cutsem (2000, p. 98) for related rings from Yemen.
The example here has excellent wear and age. It has an excellent patina. Other than wear, there are no losses.
van Cutsem, A., A World of Rings: Africa, Asia, America, Skira, 2000.