Petrified Oncolite Stromatolite Cyanobacteria Chihuahua, Mexico Cretaceous 3.75”

Description

Polished Freshwater Oncolite Stromatolite
Lady of Angels Lake, Chihuahua, Mexico
Upper Cretaceous
3.75”x3”x1/2”-3/8” slightly tapered
The oldest known Stromatolites (Cyanobacteria) date back to 3.74 Billion years. Consisting of 7/8 of all life that ever existed in the recorded fossil record. Stromatolites were the first organisms that used photosynthesis as a means for producing energy for itself, thus releasing free oxygen into the atmosphere. The very atmosphere we breath today.
Oncolites are sedimentary structures composed of oncoids, which are layered structures formed by cyanobacterial growth. Oncolites are very similar to Stromatolites, but, instead of forming columns, they form approximately spherical structures. The oncoids often form around a central nucleus, such as a shell fragment, and a calcium carbonate structure is deposited by encrustin microbes. Oncolites are indicators of warm waters in the photic zone, but are also known in contemporary freshwater environments. These structures rarely exceed 10 cm in diameter.
Condition is New. Shipped with USPS Flat Rate Package.
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