Exotic Pipes (image) University of Illinois at Urbana-Champaign Caption This Hopewell era platform pipe was discovered in Adams County, Illinois, in 1928. It is made of catlinite from Minnesota. Similar pipes were found in Tremper Mound, Ohio. Credit PHOTO: L. Brian Stauffer (ISAS artifact) Usage Restrictions Image may be used only to accompany stories about the research described in this release. Credit: PHOTO: L. Brian Stauffer (ISAS artifact) Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.