Where to Find Lake Superior Agate in Minnesota

The Lake Superior agate is Minnesota's state gemstone, and the best collecting follows the gravel pits, river bars, and glacial moraines south and west of Duluth. The North Shore beaches from Two Harbors to Grand Marais yield small, water-worn agates with red-brown and gray fortification banding, and the gravel pits around Carlton and Pine counties produce larger nodules from the original Keweenawan basalt source rock. Farther south, agate turns up in farm field gravels through Mille Lacs and Aitkin counties, carried there by the Superior lobe of the Wisconsin glaciation. Red, orange, and tube agates are typical; eye and ruin patterns are rarer prizes.