Mixed-Metal Band Ring with Dark Gemstone

This is a substantial mixed-metal band ring, likely crafted from sterling silver with yellow gold or brass accents. The ring features a wide, tapered band with a bold, architectural design characteristic of late 20th-century contemporary jewelry. At the center is a bezel-set circular dark gemstone, appearing deep purple or black, possibly onyx or amethyst. The shoulders are decorated with thick, raised horizontal ribs punctuated by rows of golden spherules or 'caviar' beading, suggesting an influence from designers like David Yurman or Lagos. The metal shows significant signs of wear, including a heavy surface patina, multiple fine scratches, and darkening in the recessed areas (oxidation). The design is stout and robust, with a thick shank that tapers slightly. No maker's marks or fineness stamps are visible from this angle, but the craftsmanship suggests a piece of designer or high-quality bridge jewelry. The ring sits atop a tangled pile of various chains and costume jewelry, indicating it is part of a larger collection or estate grouping.