sentences:  Archaen granites and gneisses, and later limestones and sandstones, are quarried for structural stone and monuments.Glacial deposits are mined for aggregates, glacial till and lacustrine deposits formed the parent soil for the state's farmlands, and glacial lakes are the backbone of Minnesota's tourist industry.These economic assets have in turn dictated the state's history and settlement patterns, and the trade and supply routes along the waterways, valleys and plains have become the state's state's transportation corridors.