mineral

Likely yellow calcite or sulfur-bearing mineral fragment

Calcite (CaCO₃) or native sulfur (S); identification is uncertain from the blurred image

AI-generated identification · may be incorrect

Small opaque yellow, earthy-to-waxy fragment with uneven fracture and no visible crystals. Calcite has Mohs hardness 3, vitreous luster, rhombohedral cleavage, and specific gravity 2.71; sulfur is softer (1.5–2.5), resinous, and lighter (about 2.0–2.1).

Identified August 15, 2026More mineral →

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At a glance

Common name: Likely yellow calcite or sulfur-bearing mineral fragment
Scientific name: Calcite (CaCO₃) or native sulfur (S); identification is uncertain from the blurred image
Category: mineral
Identified: August 15, 2026
Method: Standard

AI Estimated Value

Typically $1–$10 for a small common fragment; distinctive natural sulfur or calcite specimens may sell for $10–$50 or more.

Not an official valuation

AI estimate for general interest only — not an appraisal. Actual value depends on condition, provenance, and market demand. Verify with a professional before buying, selling, or insuring.

This identification was generated by AI and may contain errors. Verify important details before relying on them — and never use an AI result to judge whether a specimen is safe to handle. Read the full disclaimer

Physical properties

Formation & geological history

Yellow calcite forms in hydrothermal veins and sedimentary cavities; sulfur commonly forms by volcanic sublimation or bacterial reduction of sulfates. Ages vary widely with the host deposit.

Uses & applications

Calcite is used in cement, aggregate, lime, and occasionally as a collectible mineral; sulfur is used in sulfuric acid, fertilizers, chemicals, and matches. Neither appears gem-quality here.

Geological facts

A drop of dilute hydrochloric acid will effervesce strongly on calcite but not sulfur. A copper-colored streak or sulfurous odor when heated would support sulfur, though testing should be avoided without proper safety controls.

Field identification & locations

Common sources include limestone caves, hydrothermal veins, and volcanic regions worldwide. The image is insufficient for confident identification; hardness, streak, cleavage, and acid testing are useful field checks.