Archaean Banded Iron from Wisconsin

Description: This banded iron is metasediment (sediment that has undergone metamorphism) and has a high content of magnetite (Fe3O4), making it a natural magnet, also resulting in the midnight black coloration. Minute crystalline forms of other mineral-based compounds are also present; Whether the sediment was of bioorganic origin (stromatolite) is indeterminable, but likely.

The specimen has been hand-polished to a glassine finish on one side with fine carbide and diamond abrasive, a very labor-intensive job.

Stromatolites have persisted to the modern day in such places as Shark Bay, Australia where they continue their billions of years old lifestyle. While this piece would make a fine present for any natural history buff, anyone who appreciates art would also be glad to get thus wonderful specimen as a gift.

Also see: Stromatolites Across Geologic Time