sedimentary
Stromatolite
Biogenic sedimentary rock (Calcium carbonate / Dolomite)
AI-generated identification · may be incorrectMohs hardness 3-4, earthy to vitreous luster, distinct layered or laminated internal structure, colors range from gray and brown to pink.
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Physical properties
Mohs hardness 3-4, earthy to vitreous luster, distinct layered or laminated internal structure, colors range from gray and brown to pink.
Formation & geological history
Formed through the trapping and binding of sediment particles by microorganisms, primarily cyanobacteria, in shallow aquatic environments dating back billions of years.
Uses & applications
Used primarily in scientific research to study early Earth history and primitive life, and valued as a decorative collector specimen.
Geological facts
Stromatolites represent some of the oldest known records of life on Earth, with fossil examples dating back over 3.5 billion years.
Field identification & locations
Easily identified in the field by their distinctive undulating, concentric laminations; found worldwide in ancient marine and freshwater carbonate deposits.
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