What are jewels in a watch movement and is it true that movements with more jewels are better?
-D. Huntington Stamford, CT Jewels are friction reducing bearings made from synthetic rubies which are placed in high wear parts providing a nice low-friction surface in both hand-wind and automatic-wind mechanical watches. Ruby is used because it is extremely hard and provides a slick surface for the wheel pivots and other steel components of the watch movement to operate on. Synthetic rubies are used because they can be manufactured to more precise specifications than natural rubies, don’t have any inclusions, and end up doing as good as or an even a better job. The moving parts of a watch movement would quickly grind away without the protection and lubrication provided by jewels. Most manual wind watches produced today have a standard complement of 17 jewels. Automatic wind movements and movements with additional functions such as chronographs, perpetual calendars, or repeaters require more jewels due to their additional complications. Some ultra high grade or very slim movements ma
