Minnesota Brick Clay July 27, 2017 Mitch Iburg Discarded Bricks embeded in Decorah Shale Clay - found at the ruins of Twin Cities Brick Company, Saint Paul, MN. Acme/Ochs Brick Plant: Mountain of crushed brick for use as temper material. Acme/Ochs Brick Plant: Primary kaolin blended with local brick clay. Acme/Ochs Brick Plant: Beehive kiln ruins, used throughout the 1800s until the introduction of industrial car kilns. Bricks produced at the Acme/Ochs Plant (L) Cretaceous clay harvested near the plant (below R)Grog created by mechanically crushing waste brick (top R) Line Blends of Springfield, MN brick clay with primary kaolin.