Tektite or dark stone specimen

This object is a dark, irregularly shaped nodule held in the palm of a hand for scale, appearing roughly a few inches in length. The material exhibits a deep charcoal black to dark greenish-black coloration with a highly textured, pitted, and uneven surface showing micro-depressions and undulating ridges. There are no clearly legible maker's marks, hallmarks, or signatures visible from this angle, and the identification is based entirely on visual similarities to natural glass tektites or dark mineral specimens. The item displays a matte to slightly vitreous luster across its rugged topography. Regarding condition, it presents standard natural surface wear, inclusions, and pitting consistent with an unpolished geological or impact-derived specimen rather than manufactured jewelry, though the user-supplied attribution places it in the jewelry category as an unverified claim. The identification rests purely on the visual appearance of a dark, textured natural stone and remains unauthenticated.

Per user submission, this object is categorized under jewelry and visually resembles a dark tektite or geological specimen. Based on what I can see in the photograph, the item presents a deep charcoal black coloration and a rugged, pitted, and uneven surface texture with undulating ridges. I cannot verify from a photo the exact mineral composition, geological origin, or whether the material is a natural tektite, impact glass, or a synthetic imitation, as physical inspection and scientific testing would be needed to confirm these characteristics. My value estimate of $50 to $150 assumes the unverified working hypothesis that the specimen is a natural, collectable tektite or similar geological stone suitable for jewelry use. General market demand for unmounted, unpolished natural tektites or dark mineral specimens typically occupies this modest range among collectors and amateur lapidaries. If physical examination reveals the piece to be a modern glass replica, industrial slag, or a synthetic imitation rather than a natural specimen, the market value would drop significantly, likely to nominal decorative value under $20. To establish the true nature, composition, and potential value of this item, an in-person examination by a qualified gemologist or geologist, alongside potential specific gravity testing or microscopic analysis, would be necessary.