The "jewels" in a jeweled movement watch are not the ones that you see on the outside. Polished jewel "bearings" are created for the moving parts inside the watch. If all of the moving parts were "metal on metal", the watch would wear out much sooner. Jeweled movement watches last longer and are able to go longer between maintenance.
Not all watches have jewels inside them. While many mechanical watches use synthetic rubies or sapphires as jewels to reduce friction and wear in the movement, quartz watches often do not require them due to their different operating mechanism. Therefore, while jewels are common in higher-end mechanical watches, they are not a universal feature in all types of watches.
Generally they are unless they are electronic watches.
There's a good discussion of jewels in watches here: http://elginwatches.org/help/watch_jewels.html
Highwaymen would steal anything of value (money, jewels, watches, etc).
The number of jewels do not correlate to water resistance.
Typically, Gucci watches that do not contain gold or diamonds are in the range of $300-$600. More expensive watches contain precious metals or jewels. These can be sold anywhere from $800-$1500
A person who sells jewels is called a jeweler.
The numbers of jewels that are referred to in watch movements all depends on the make and manufacture of the watch. Certain companies like Waltham used extra jewels in the mechanisms of their watches, and 19 was referred to as a 19 jewel movement.
Clock jewels are the bearings used in expensive spring-wound clocks and watches, so called because they use a natural or synthetic jewel surface such as ruby or sapphire.
Jewels are used in watches at friction points. You can get them to a very fine point and they will not wear down like metal. So at a point that a gear will be turning for days and days, they use a jewel. if they used metal the point would soon wear to a round nub. Like the end of a ball point pen. increasing friction, and slowing the watches movement. Decreasing the accuracy of the watches timekeeping ability. Usually the higher amount of jewels in a watch the more accurate. Also more moving pieces. Historically the more jewels the more expensive. That was when all the watch pieces were made by hand, and needed to be very precise. Now that we have CNC and computers making very precise components, that old adage isn't so true. Jewels are used in all watches that have gears and movements in them. Not just Automatic watches. The newer watches that are basically small printed circuits and LED readouts don't have them, because of no moving parts. And I'm not sure if new cheap watches with moving hands, they may have little electric motors. But if it is old, or new and you can see moving gears when you remove the back. It has "Jewels".
Jewelry? AKA rings, watches, bracelets, jewels, gems, necklaces, gold, silver, pandora's etc
Person who designs, makes, sells, or repairs jewelry, watches or a person who deals with jewels called "jeweler".