Over one billion years ago, the middle of the continent began to rip apart. When this occurred a number of new rocks formed, including one rock type found only a few places on earth. They have subsequently been shaped by other tectonic events and glaciers. We examine the rocks, record observations and then interpret the data to unravel one part of the history of Minnesota. Specific rocks are the focus of subsequent labs on the geochemistry of volcanic rocks and phase diagrams.