Is it better to do stone grinding, granite or bluestone?

Bluestone is better than granite, because the hardness of bluestone is higher than sandstone, while granite absorbs water, is not resistant to weathering, is easy to break, has low hardness and poor grindability.

Extended data:

Stone mill is a machine used to process rice, wheat, beans and other grains into powder and pulp. Began to use human or animal power, and in the Jin Dynasty, China was old.

People invented the waterwheel powered by water. Usually made of two round stones. Grinding is a two-layer plane, and the junction of the two layers is textured.

Particles enter the middle of the two layers from the upper hole, move outward along the particles, and are ground to form powder when rolling through the two layers.

Traditional stone mill

1968, a stone mill, a stone mill group and a copper funnel were unearthed from the Manchu Han Tomb in Baoding City, Hebei Province, about 2 100 years ago.

Copper-stone compound grinding. This is the earliest stone mill discovered in China so far.

Modern stone mill

Modern stone mill retains the grinding part of traditional stone mill, that is, two cylindrical rocks, and changes the traditional power generation device from the original.

The power of donkey milling is changed into the power of motor milling, and at the same time, a conveying device and a cleaning device are added.

Compared with the traditional stone mill, the modern stone mill saves labor, reduces the amount of labor and improves the output of the stone mill.

References:

Baidu Encyclopedia-"Stone Mill"