May 22 Gifts from Lake Superior

I grew up in Duluth, MN and spent many hours along the shore of Lake Superior with my family searching for bright red spots among the rocks. Tonight, as I arrived in Duluth for a visit, we returned to our old ways. Although we were hoping to spot a red-throated loon rumored to be along Park Point, we were instead rewarded with this pretty, banded agate. Lake Superior agates, like most rocks I suppose, have a long history. About a billion years ago, the North American continent began to split apart, creating lava flows that eventually became the Lake Superior basin. As the lava hardened into rock, gas bubble became trapped, and turned into molds for the lovely agates. As groundwater (filled with various minerals like red iron and white quartz) slowly seeped into the holes, the ground water solutions crystallized, creating the different colored bands for which agates are known. Thanks to the glaciers, which moved rocky material, these Lake Superior agates can now be found far away from the shores into central Minnesota and parts of Wisconsin.