fossil

Fossilized stromatolite or laminated microbial mat

Layered carbonate/chert fossil; exact taxon indeterminate from the image

AI-generated identification · may be incorrect

Gray-brown, irregular specimen with pronounced folded, wavy laminae and dull to slightly earthy luster. Likely Mohs 3–7 depending on whether it is carbonate or silicified; no reliable cleavage is visible.

Identified August 16, 2026More fossil →

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Physical properties

Formation & geological history

Formed when microbial mats trapped and bound sediment, producing repeated layers later lithified and possibly silicified. Stromatolites range from Precambrian examples over 3 billion years old to modern formations.

Uses & applications

Primarily a teaching and collecting specimen; polished examples are decorative. Value is generally modest unless locality, age, and authenticity are documented.

Geological facts

The distinctive contorted layering resembles stromatolitic laminations, though similar textures can occur in folded sedimentary rock or banded chert.

Field identification & locations

Look for repeated, organically curved laminae unlike ordinary bedding, plus a rock-like mineralized texture. Common sources include ancient carbonate platforms and Precambrian terrains in Australia, Canada, South Africa, and the United States; a locality label is essential for firm identification.