https://iowageologicalsurvey.org/wp-content/uploads/2019/09/Core-Sample-Tim-Schoon-photo.jpg427640rtiwarihttps://iowageologicalsurvey.org/wp-content/uploads/2018/10/igs-logo-300x116.pngrtiwari2019-02-18 17:48:252020-06-26 11:04:38Are there valuable, un-mined minerals in Iowa?