Ohio Rocks - Geology, Ice Age, Fossils, and Resources (Full)
29:01
Ohio's Scenic Geology
20:53
Continents Collide: The Appalachians and the Himalayas
16:56
Ohio's Scenic Geology - Short Take
36:55
Appalachian Geology: Surprising Implications
19:17
Rock and Mineral Identification
21:15
Mining for Ohio's Gemstone
18:11
Ohio's Hidden Mine
8:32