Grypania spiralis

Nice! Is this yours?

Where did you get one of these??

17 hours ago, connorp said:

Nice! Is this yours?

Yes  

9 hours ago, Wrangellian said:

Where did you get one of these??

IRL and not online, surprisingly!

Wow.. that's even harder to believe.... I'm not traveling in the right circles. Being in North America is obviously no advantage.

These can't be that common - I understand they mined some from deep underground, then closed the mine, so there won't be any more.

5 hours ago, Wrangellian said:

These can't be that common - I understand they mined some from deep underground, then closed the mine, so there won't be any more.

Definitely, it's the first one I've ever seen up for sale too.

Very nice! It seems to me a tectograph (see Seilacher et al 2000) not a body or a trace fossil...

3 hours ago, ana zucatti said:

Very nice! It seems to me a tectograph (see Seilacher et al 2000) not a body or a trace fossil...

This is a textbook example of Grypania spiralis that matches perfectly with regard to morphology and the lithology from the Negaunee Iron Formation near Marquette, Michigan.  About 10 years ago the Potomac Museum Group made a few dozen of these specimens available for sale.  Most of the stratigraphic samples taken in the mine during the excavation were 'float' pieces that never received an accession number for the PMG collections.  Additionally, I had the good fortune to acquire a similar plate of G. spiralis directly from one of the specialists that was working with the PMG research group at the time they were first offered publicly for sale.  For further suggested reading and comparison, the attached figures are from:

Han, T.M., & Runnegar, B. 1992

Megascopic eukaryotic algae from the 2.1-billion-year-old Negaunee Iron-Formation, Michigan. Science, 257:232-235

5 hours ago, piranha said:

 

 

This is a textbook example of Grypania spiralis that matches perfectly with regard to morphology and the lithology from the Negaunee Iron Formation near Marquette, Michigan.  About 10 years ago the Potomac Museum Group made a few dozen of these specimens available for sale.  Most of the stratigraphic samples taken in the mine during the excavation were 'float' pieces that never received an accession number for the PMG collections.  Additionally, I had the good fortune to acquire a similar plate of G. spiralis directly from one of the specialists that was working with the PMG research group at the time they were first offered publicly for sale.  For further suggested reading and comparison, the attached figures are from:

 

Han, T.M., & Runnegar, B. 1992

Megascopic eukaryotic algae from the 2.1-billion-year-old Negaunee Iron-Formation, Michigan. Science, 257:232-235

 going to have to peep your collection thread again to check out your G. spiralis specimen!