Iron Range Stromatolites

Notes specific to this specimen: You will receive an obelisk very similar to this one shown.  We fashion only a limited number of obelisks out of this material because in the process we lose a lot of material.  Even so, it is sometimes worth it as the cutting of obelisks creates a great 3-D view of the colonies.  Here we have deep red agatization in these longitudinally cut colonies.  These specimens attest to the classic origin of this material from the old Mary Ellen Mine in Biwabik, Minnesota, the type locality for the Biwabik Iron Formation. The mine shut down over 50 years ago. We find the material in the old discard piles that surround the pit.

Size: 2.25″ x 3″ tall

Name / Species: Collenia undosa
Age: Paleoproterozoic – 2.1 billion years
Unit: Biwabik Iron Formation
Site: Biwabik, Minnesota
Collected: 1992
Collected by: Jon Kramer

Documentation: This authentic fossil specimen comes with a Certificate of Authenticity and Origin. In addition, an attractive and informative display card accompanies the specimen.

Notes specific to this specimen: You will receive an obelisk very similar to this one shown.  We fashion only a limited number of obelisks out of this material because in the process we lose a lot of material.  Even so, it is sometimes worth it as the cutting of obelisks creates a great 3-D view of the colonies.  Here we have deep red agatization in these longitudinally cut colonies.  These specimens attest to the classic origin of this material from the old Mary Ellen Mine in Biwabik, Minnesota, the type locality for the Biwabik Iron Formation. The mine shut down over 50 years ago. We find the material in the old discard piles that surround the pit.

Size: 3.25″ x 4″ tall

Name / Species: Collenia undosa
Age: Paleoproterozoic – 2.1 billion years
Unit: Biwabik Iron Formation
Site: Biwabik, Minnesota
Collected: 1992
Collected by: Jon Kramer

Documentation: This authentic fossil specimen comes with a Certificate of Authenticity and Origin. In addition, an attractive and informative display card accompanies the specimen.