====== Jewels ======
{{wst>image_l|Chaton|Screwed [[chaton]] at a movement of\\ [[A. Lange & Söhne]] with red **ruby** or **jewel**|240px}}
A **jewel** is a component of a [[watch movement]].

**Jewels** are synthetically produced [[ruby|rubies]], which are used to reduce friction in the main bearings of the moving parts of a [[watch movement]].

[[Quartz watch]]es with few moving parts have only a few jewels, mechanical watches have 17 to about 50 jewels depending on the complexity of the movement.

Jewels are used as **hole stones** or **capstones**, and in addition also at [[lever]] pallets and at the ellipse.

A lot of jewels in a movement does not necessarily signify a higher quality. On the contrary, often cheap wristwatches with a high number of jewels noted on the dial intend to suggest a high quality. However, many of these are not really needed or are not at the necessary places. A precision movement with [[manual winding]] needs at least 15 functional jewels 10 jewels, 2 capstones for the [[balance wheel]], 2 pallet stones for the [[lever]] and one impulse stone (ellipse). An optimum configuration is given with 18 jewels.

For complicated watches such as with [[automatic winding]], [[chronograph]] or [[repetition]], the number of jewels necessarily increases.


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