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Red granite at Copper Falls State Park; Wisconsin. Photo by Aaron Carlson/Flickr (Use Permitted with Attribution/Share Alike).
Official State Rock of Wisconsin
Wisconsin designated red granite as the official state rock in 1971 (Wisconsin also adopted a state mineral; galena).
Red granite was proposed as a state symbol by the Kenosha Gem and Mineral Society to help promote awareness of Wisconsin's geology. All State Rocks & Minerals
Wisconsin