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Synthetic stones for watchmaking

Watchmaking stones, also known as rubies, are small synthetic stones generally composed of ruby, sapphire or sometimes synthetic corundum.

They are used in the manufacture of mechanical watches as bearings for the pivot points of gears and other moving parts.

These stones perform several important functions in a watch movement:

Reduce friction:

The primary function of gemstones is to reduce friction between the moving metal parts of the watch movement.

The stone’s extremely smooth, hard surface provides a low-friction interface for the rotating metal pivots of the gears, reducing wear on the movement over time.

Improving sustainability :

As stones are much harder than metal, they are highly resistant to wear.

By using gemstones as bearings, watchmakers can significantly increase the life and reliability of a watch movement, as they provide a durable, long-lasting surface against which the pivots rotate.

Improved precision :

By reducing friction and wear on the movement, the stones contribute to the overall precision of the timepiece.

Smoother, smoother movement of the gears translates into more accurate timekeeping.

Reduced lubrication requirements :

Compared to metal-to-metal bearings, ball bearings require minimal lubrication. This is because the hard, smooth surface of the rubies creates less friction, reducing the need for frequent oiling or greasing of the watch movement.

This means longer service intervals and a more reliable timepiece.

Shock absorption :

In addition to reducing friction, watch jewels also help absorb shocks.

This protects the delicate mechanical components of the watch movement from damage caused by sudden impacts or vibrations.

Overall, rubies play a crucial role in the performance, durability and longevity of mechanical watches.

They are a key element in the construction of the movement, and are carefully selected and positioned by watchmakers during the assembly process to ensure optimum performance.