Gathering Samples (image) American Society of Agronomy Share Print E-Mail Caption In this photo, a middle school researcher gathers samples of calcium carbonate for testing. Credit David C. Weindorf. Usage Restrictions Please use with story only. Share Print E-Mail 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.