Sapphire Washers Wafer Bearings windows Rods Tubes Ruby jewel bearing for watch

In 1704, Nicolas Fior di Duillier, Peter Debaufre and Jacob Debaufre pioneered the gemstone bearing, they bored a hole in gemstone, and then placed  gear shaft into the hole. That reduced the friction between the movement of the gear and the splint to a certain extent,  . At that time the use of precious stones is not limited to rubies, but diamonds. Sapphire. Garnet ... ... ... ... The reason is why choose precious stones, just for mechanical properties.
After the 1930s, artificial rubies bearing applicated in large-scale. It is because  artificial rubies property of hard, Chemically stable, Friction coefficient, Small thermal expansion coefficient, low price, easy to manufacture and cost-effective. It is the most appropriated soluting to reduce  friction movement.