Art Deco style silver-tone ring with square purple stone and marcasite

This is a decorative ring worn on the finger, featuring a geometric, elongated cluster design typical of the Art Deco aesthetic. The piece is crafted from a dark, oxidized or patinated metal, consistent with vintage sterling silver jewelry settings. At the center is a pale purple, square-cut or rectangular-cut transparent gemstone, possibly an amethyst or a synthetic spinel, held securely by corner prongs. The setting surrounding the central stone is heavily embellished with small, round, faceted dark stones that resemble marcasite, set flush into an intricate, openwork milgrain or textured metal framework that tapers toward the band. There are no maker's marks, hallmarks, or signatures directly visible from this photographic angle, so the attribution rests entirely on the stylistic visual characteristics, including the geometric symmetry and filigree detailing. The overall condition shows a natural dark patina to the metal surfaces and minor surface wear consistent with age and prior use. This item is unauthenticated and unverified, and its precise metal purity, gemstone identity, and era of manufacture remain unconfirmed.

Based on what I can see in the photograph, this ring exhibits stylistic features typical of the Art Deco period, including a geometric elongated cluster design, openwork filigree, milgrain detailing, and what appears to be marcasite accent stones surrounding a pale purple central gemstone. However, I can't verify from a photo alone the precise metal purity, gemstone identity, or era of manufacture. There are no visible hallmarks or maker's marks from this angle, and I would need physical inspection to confirm whether the metal is sterling silver, the central stone is a natural amethyst or synthetic spinel, and the accent stones are genuine marcasite. My value estimate of $150-$300 assumes that the piece is a vintage sterling silver and marcasite ring from the Art Deco era. Market demand for vintage Art Deco revival and period jewelry remains steady among collectors of antique accessories, though unauthenticated pieces without maker's marks generally trade at more modest price points. If physical examination reveals the item to be a modern reproduction, replica, copy, or produced simply 'in the style of' the period using base metals and simulated stones, the market value would likely decrease significantly to the $30-$75 range. To establish authenticity, a definitive era of manufacture, and material composition, a physical examination by a qualified gemologist or jewelry appraiser, along with possible acid testing or gemstone testing, would be required.