A yooperlite stone is a sodalite-syenite rock that glows orange-yellow under ultraviolet (UV) light. Discovered in the Upper Peninsula (UP) of Michigan in 2017, the name "yooperlite" comes from the local term "Yooper" for people from the UP. These rocks were transported from Ontario, Canada, by glaciers and are found along the shores of Lake Superior, particularly after storms that uncover them.