Rock Identifier
Likely polished dark stone or glassy mineral bead (Indeterminate; possibly obsidian, hematite, or a dark agate) — mineral
mineral

Likely polished dark stone or glassy mineral bead

Indeterminate; possibly obsidian, hematite, or a dark agate

AI-generated identification · may be incorrect

Small, smooth, rounded specimen with dark gray-black color, subdued vitreous-to-waxy luster, and a pale concentric/linear pattern. Hardness cannot be determined reliably from the image; likely about Mohs 5–7 if stone, though it may be a manufactured bead.

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Physical properties

Small, smooth, rounded specimen with dark gray-black color, subdued vitreous-to-waxy luster, and a pale concentric/linear pattern. Hardness cannot be determined reliably from the image; likely about Mohs 5–7 if stone, though it may be a manufactured bead.

Formation & geological history

If natural, obsidian formed as rapidly cooled volcanic lava, while agate formed when silica-rich fluids filled cavities; hematite formed in oxidizing hydrothermal or sedimentary environments. Geological age depends on its source and cannot be inferred visually.

Uses & applications

Polished specimens are used as curios, beads, cabochons, and decorative objects; obsidian and agate are also collected as lapidary materials.

Geological facts

The smooth oval shape and apparent drilled or centered feature suggest a polished bead or cabochon rather than an unmodified rock. The image is too blurred for confident mineral identification.

Field identification & locations

Check for a drill hole, perfectly uniform polish, glass-like conchoidal fracture, streak, and hardness against glass. Natural obsidian commonly shows sharp fractures; agate generally reveals translucent banding.