Gunflint Iron Rainbow Stromatolite

IMPORTANT NEW DISCOVERY – This incredible fossil material was just discovered in 2025 and has never before appeared on the market! These are from a new discovery we made of multicolored fossil stromatolite in the Gunflint Iron Formation (GIF) of Ontario. If you’re a fan of Early Life fossils, then you probably know the Gunflint Iron Formation is an ultra famous Konservat-Lagerstatten that upended the science of paleontology in the 1950s when fossils of microorganisms were discovered in its chert beds. At the time, the notion of fossils predating the Cambrian was flatly unaccepted and the announcement was met with great skepticism.

But in 1954 researchers Stanley A. Tyler and Elso S. Barghoorn published their seminal work “Evidence for the Existence of Life in the Early Precambrian Rocks of Northern Ontario” where they described unequivocal silicified microfossils found in Gunflint Chert dating to about 1.8 billion years ago. Those fossils became the first widely-accepted and scientifically confirmed Precambrian biota and were a turning point in establishing the existence of early life deep into the Precambrian of Earth history.

Fossils from the Gunflint Iron Formation are microscopic and not easy to come by. We have collected GIF specimens since the 1980s, even from the type locality of Gunflint Lake, which we have visited many times. But we have never collected anything other than shale and chert with microscopic specimens. While the Gunflint is known for its invisible prokaryotes, it is definitely not known for macrofossils. This site, in a very remote region of the North Woods, represents the only known occurrence for such incredible – and beautiful – stromatolites within the Gunflint. By purchasing a specimen you will own a piece of paleontological history and will help us in preserving this unique site. As with all our sites, specimens of scientific importance are DONATED to museums, schools, and research facilities around the world.