Wiki-Artificial whetstone

In contrast to natural grinding wheels, which are formed over a long period of time by sedimentation, synthetic grinding wheels are made by hardening abrasive grains and a binder through artificial processes such as baking and drying. While most natural grinding stones are expensive, especially for finishing wheels, artificial grinding stones are relatively inexpensive and can be made homogeneous throughout. There are a wide variety of artificial grinding wheels with varying degrees of hardness and grinding power, depending on the combination of abrasive grains, bonding agents, and manufacturing methods.

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