Grinder is a machine that has functioned through history by hand, horse, water, wind and electricity. It is used to break down hard products into particles. In the past they were made in two parts, the floor that was flat and static to hold the product and the grinding stone, the upper piece that was turned so it rolled and crushed what was between them.
Above from left to right:
Grinding olives: Grinding grapes: Chemist mortar: Grinding corn.
Ball mill is an electrically controlled machine that turns, grinds and mixes materials.
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