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    Collenia undosa
    Precambrian (Proterozoic)
    Biwabik Formation, Mary Ellen Mine, Mesabi Range, St. Louis County, Minnesota

    Stromatolites are colonial structures formed by photosynthesizing cyanobacteria (blue-green algae) and are the oldest known fossil organisms dating back over three billion years! They were the dominant life form for over two billion years, and it is theorized that oxygen-producing cyanobacteria were responsible for the creation of the Earth's original atmosphere. These stromatolites date back over two billion years, and they are found in association with iron mines in northern Minnesota where it is now apparent that they played a key role in the formation of the Mesabi Iron Range.Mineral replacement of these colonies by red agate (Quartz) and metallic iron (Hematite) resulted in this beautiful material. Known commonly as "Mary Ellen" Jasper for the mine of the same name, this material is a rich, deep opaque red agate with tinges of black and is exceptionally beautiful when cut and polished to reveal its full potential. This elegant sphere measures 8 inches (20.32 cm). For a primitive life form, Collenia is an exquisitely beautiful fossil. Offered at no reserve.

    [Scale: 1 inch, with mark at 1 cm]

    Condition Report*: Condition report available upon request.
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    Auction Info

    Auction Dates
    June, 2013
    2nd Sunday
    Bids + Registered Phone Bidders: 4
    Lot Tracking Activity: N/A
    Page Views: 1,328

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