Chert: Chert has the same chemical composition as quartz.
Continental Glaciers: Large accumulations of ice that moved, due to the force of gravity, to cover large areas (hundreds of thousands of square miles).
Dolomite: Dolomite was originally limestone that became rich with magnesium.
Esker: Long, narrow, commonly sinuous ridge of glaciofluvial material deposited in a subglacial ice tunnel or ice walled channel.
Fault: A fracture or series of fractures upon which there has been horizontal and/or vertical movement of rock layers.
Glaciation: Shorter time periods, tens of thousands of years) during which glaciers were at their maximum extent.
Hammermill Crusher: Slinging hammers on a rotary shaft crush the rocks until the rocks reach clearance and are able to pass through a series of ten sieves.
Ice Ages: Intervals of time when large areas of the surface of the globe are covered with large continental glaciers that advance and retreat.
Impact Crusher: Crusher that alternates between stone ñ steel ñ stone crushers until the rock being crushed passes clearance.
Kame: Steep-sided hill or ridge of glaciofluvial debris deposited in contact with glacier ice.
Lamination: Net deposition of sediment on flat, sandy stream beds produces horizontal layers.
Limestone: deposits of materials (fossils and sediments) compress Lime Mud and minerals (mainly calcite) until it is transformed into limestone.
Primary Clearance: 2 ¼ inch sieves in which rocks can pass through.
Secondary Clearance: 7/8-inch sieves in which rocks can pass through.
Segregation: Coarser sediments flow differently than finer sediments through the mix loaders and surge piles have differentiation. Fine sediments lie at the top at the pile while coarser sediments flow down to the bottom of the pile.
Wash Rock: Tile or decorative stone.
Wisconsinan Glaciation: The youngest glacier that reached into central Illinois.