In the 1950's The Waltham Watch Company of Waltham, Mass introduced a 100 jewel watch. Only 17 of the jewels were functional meaning those 17 jewel were placed between the gears of the watch to reduce friction, hold lubricant longer , reduce the amount of lubricant needed, increase temperature stability and reduce corrosion. (All reasons jewels are used in movements today) There were two cap jewels, two pivot jewels, an impulse jewel for the balance wheel, two pivot jewels, two pallet jewels for the pallet fork, and two pivot jewels each for the escape, fourth, third and center wheels. The remaining 83 jewels were simply placed at the edge of the automatic rotor (seen above). These jewels had absolutely no function and so created the watch with the most amount of non-functional jewels. Although there is a space for a 101th jewel on the automatic rotor, the space is vacant as 101 jewels does not sound as marketable as 100 jewels.
The Walthman Watch Company closed its doors in 1957 as a result of financial stress and less than perfect craftsmanship, it seems the 100 Jewel Watch was its last desperate attempt to make a sale. The company relied on the fact that many people believed the more jewels the more precise the watch movement. People may have believed the jewels were actually worth something.
In fact most jewels are synthetic costing very little and the jewels themselves are worth very little.
In the 1940's and 1950's many companies were upping there non-functional jewel count without increasing the complications. Between 1902 and 1965 it was "anything goes" in regard to the amount of jewels in a watch movement. In addition the amount of jewels were stated on the dial as a marketing ploy. Then in October 1965, the Swiss organization NIHS - Normes de I'industrie Horlogre Suisse, whose function was to develop the standards for the Swiss Watch Industry, published a standard (NIHS 94-10) in order to control the way in which the number of jewels in a movement are used in advertising and any sales related to horology and timekeepers. In 1974, the NIHS and ISO 1112 which was recently updated in ISO 1112:2009 specifies the technical definitions of functional and non-functional horological movement jewels. In addition it describes the different types of jewels used, and how this is to be marked on a timekeeping instrument or used in advertising. In this way the type of jewels used, the amount of jewels used and the way in which the jewels can be used to increase the jewel count of the watch is outlined.
Today the more jewels indicate more complications as there are more moving parts. The more jewels used, the less the wear and tear on the watch parts. Many watch companies use 21 jewels and some ETA movements use 25 jewels. The jewels themselves are valued at very little since most are synthetic; however, it is the well placed functionality in conjunction with superior craftsmanship of the watch part that attract watch enthusiasts and horology admirers.