Ring in the style of an onyx and gold signet

This item appears to be a yellow-toned metal signet-style ring featuring a dark, opaque stone center. Based on visual characteristics, the stone is consistent with black onyx or a similar glass or resin substitute. The stone is shaped into a flat, elongated hexagonal or octagonal tablet with beveled edges, held in place by a bezel or semi-bezel setting that integrates into the shoulders of the band. The metal exhibits a yellow color consistent with gold or gold plating, and there appear to be small white-toned accents—possibly minute diamonds or synthetic stones—set into the decorative shoulders. The band follows a tapered design, narrowing toward the back of the finger. Conditions observed include slight surface wear and minor scuffing on the flat face of the stone, which is common for vintage-style jewelry. No maker's marks, hallmarks, or metal purity stamps are legible in the provided photograph, making a definitive identification of material and origin impossible without physical inspection by a professional jeweler. Stylistically, the piece shares characteristics with mid-20th-century or Art Deco-revival jewelry, though this is a hypothetical attribution based solely on the silhouette and construction style visible in the image.

I have examined the provided image of a signet-type ring featuring a dark, tablet-cut stone set in a yellow-toned metal band with white-toned shoulder accents. Based on what I can see, the design is consistent with mid-20th-century or Art Deco-revival aesthetics. The value range assumes the hypothesis that the metal is 10k or 14k gold and the stone is black onyx. The lower end reflects the possibility of lower gold purity and synthetic accents, while the higher end reflects potential for 14k gold and minute natural diamonds. I cannot verify from a photo the specific metal purity, the nature of the stone center, or the identity of the white accents. The value is highly dependent on material verification; if the piece is gold-plated or uses resin substitutes, the value would likely drop to the $30 - $75 range as a decorative fashion item. General market demand for vintage-style signet rings remains stable, particularly for those with geometric silhouettes. However, because no hallmarks or maker's marks are legible, I cannot attribute this piece to a specific manufacturer. To reach a more precise valuation, a physical inspection is required to test metal fineness, perform gemological testing on the stones, and search for internal stamps. Authentication of materials via scientific testing or in-person expert appraisal would be necessary to substantiate the higher estimate provided. This estimate is a working hypothesis based solely on the visual profile of the item.