HOUSTON – (May 25, 2023) – Visually striking layers of burnt orange, yellow, silver, brown and blue-tinged black are characteristic of banded iron formations, sedimentary rocks that may have ...

MADISON — The strikingly banded rocks scattered across the upper Midwest and elsewhere throughout the world are actually ambassadors from the past, offering clues to the environment of the early ...

Chert — microcrystalline silica that has been compacted and cemented into rock — is preserved extensively within rock layers of Archaean age (that is, more than 2,500 million years old) on ...

Object Details Collector Dr. Kennth B. Tankersley Donor Name Estate Of John D. Holland Notes L-1225 (Attica Chert): Collection includes raw material, outer surface, and naturally-weathered specimens.

University of Wisconsin-Madison. "Banded Rocks Reveal Early Earth Conditions, Changes." ScienceDaily. ScienceDaily, 12 October 2009. <www.sciencedaily.com / releases / 2009 / 10 / 091011184428.htm>.