Crushing is often performed on bulk field samples of harder materials like ores, minerals, and rock. Particle sizes for crushed materials tend to have a wide distribution from coarse to fine with most materials. For these reasons, sample preparation often moves on after crushing to pulverizing and milling operations.


Jaw Crushers are the most commonly used in this classification, and consist of a stationary plate with an opposing moving jaw plate. Reduction takes place as material is trapped in the gap between the two plates and fractured with compressive force. Particle size can be controlled by adjustment of the width, or gap, between the jaws. Larger particles break multiple times, starting at a higher point between the plates, then repeatedly as they drop lower into the v-shaped gap and are trapped again. Cone Crushers have a gyrating cone shaped spindle that traps particles against a mantle to crush them. The Double-Roll Crusher uses two heavy steel rolls turning in opposite directions to pull material down between the cylinders for crushing.