Calcite

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Colorless semi lustrous translucent grouping of scalenohedral calcite crystals. Slightly reddish brown in color due to iron oxides. In good condition. Neat locality example.The Lakeside Lavas consist of a series of fine-grained, pink to dark basaltic and andesitic volcanic flows that formed roughly 1.1 billion years ago during the Keweenawan rifting event along the Midcontinent Rift System. Exposed primarily along the North Shore region in St. Louis County near Duluth, these ancient flows feature vesicular tops containing secondary minerals like quartz, calcite, and zeolites. While the area lacks major commercial mining operations for these specific volcanic units, the rocky outcrops and nearby glacial drift have long served as popular sites for rockhounding, amateur mineral collecting, and geological study of Lake Superior's volcanic heritage.