Banded Tiger Iron – Beautiful slice of cyanobacteria bloom deposits (aka banded iron). Specimen measures 10” x 10” x 3/8” thick and has been polished to a glass-like finish. It displays alternating layers of hematite, oxidized iron bands, and yellow tiger-eye. To explain the alternating layers of dark and light bands, current theory holds that photosynthesizing cyanobacteria enriched the surrounding water with oxygen during a “bloom”, causing oxidized sediments to accumulate (lighter bands). When the “bloom” subsided, less oxygen was available and a more reduced band of iron accumulated (dark bands). All of these layers were deposited horizontally. Billions of years of faulting and torqueing distorted the layers to their present configuration.
Specimen has beautiful color and exceptional detail!