Archaean Stromatolites from Wyoming

Archaean stromatolites are hard to come by, especially those retaining banded laminae structure as we here. Almost certainly, the marginal marine environments of Earth contained prodigious stromatolites during the Arachaean. In fact, some theories hold that stromatolites actually peaked on Earth in the Lower Proterozoic, and steeply declined beginning by the Middle Proterozoic. However, either little of it is exposed, or what is exposed is in desolate locations. Clearly much has been ground up into sediment, otherwise distorted and perhaps subsumed into the Earth's mantel.

This beautiful specimen has ostensibly escaped much of the Earth's ravaging forces for some 2,600,000,000 years. Note the distinct wavy to subdomal form genera (laminae) made vivid and colorful on the hand-polished side. The obverse side has been left natural.