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Collenia undosa Walcott 1916 & Gunflintia grandis Barghoorn, 1965 , Eoshaera tyleri Barghoorn, 1965

Collenia undosa Walcott 1916 & Gunflintia grandis Barghoorn, 1965 ,  Eoshaera tyleri Barghoorn, 1965
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Collenia undosa Walcott 1916 & Gunflintia grandis Barghoorn, 1965 ,  Eoshaera tyleri Barghoorn, 1965
Collenia undosa Walcott 1916 & Gunflintia grandis Barghoorn, 1965 ,  Eoshaera tyleri Barghoorn, 1965
Collenia undosa Walcott 1916 & Gunflintia grandis Barghoorn, 1965 ,  Eoshaera tyleri Barghoorn, 1965
Collenia undosa Walcott 1916 & Gunflintia grandis Barghoorn, 1965 ,  Eoshaera tyleri Barghoorn, 1965
Collenia undosa Walcott 1916 & Gunflintia grandis Barghoorn, 1965 ,  Eoshaera tyleri Barghoorn, 1965
Collenia undosa Walcott 1916 & Gunflintia grandis Barghoorn, 1965 ,  Eoshaera tyleri Barghoorn, 1965
Collenia undosa Walcott 1916 & Gunflintia grandis Barghoorn, 1965 ,  Eoshaera tyleri Barghoorn, 1965
Collenia undosa Walcott 1916 & Gunflintia grandis Barghoorn, 1965 ,  Eoshaera tyleri Barghoorn, 1965
Collenia undosa Walcott 1916 & Gunflintia grandis Barghoorn, 1965 ,  Eoshaera tyleri Barghoorn, 1965
Collenia undosa Walcott 1916 & Gunflintia grandis Barghoorn, 1965 ,  Eoshaera tyleri Barghoorn, 1965

Products description

Here is a very nice Stromatolite plate from the deep Precambrian of the USA,
Es is a polished slap with the speices Collenia undosa from the about 2.2 Billion years old  Biwabik-Iron-Formation of Minnesota.
This plate shows a diverse fauna of microfossils.
Due to the partly opaque properties of this sample, these fossils are also visible without thin-section preparation.
As species are here only Gunflintia grandis Barghoorn, 1965 and Eoshaera tyleri Barghoorn, 1965 mentioned. But from the Biwabik Fm. As well as same aged Gunflint Formation are remarkably rich species community described.
It is just fascinating how early diversity can be found in the evolution of life. And above all, how well it can be still be proven after all that time.

The Site of the Mary Ellen Mine is a classical Banded Iron Formation. Locality. It is knon and valoured for its nice and colourfully preservation. These decorative Stromatolite fossils are sometimes even used for jewellery.
The Cyanobacteria that where incorporated in the bounding of this Stromatolite have likely produced significant amounts of oxygen. This free oxygen bond the FeČ that was solved in the ancient oceans. This process produced the Banded Iron Formations (also known as BIF’s ) world wide at that time in earth history. After all the iron was used up by that process the oxygen concentrations in the Atmosphere and ocean could rise. What lead to the great oxygen crisis  (sometimes also known as the first big extinction). How ever the higher levels of oxygen allowed the life eventually to become more complex.
 
 
 

Location:

Mary Ellen Mine, Mesabi Range, St. Louis County, Minnesota, USA 
Size :about 110 x 91 mm
Age:Precambrian, Lower Proterozoic, Rhyacian, Biwabik Formation  (about 2.2 Ga / 2200 Ma)

Shipping time: 3-4 Days
Product no.: 10459
220,00 EUR
7 % VAT incl.