What is the jewel count mean?

Sorry all, I am new and trying to learn.

I am seeing several different jewel counts on these watches.  What does the jewel count mean?

my watch is a 1965 23 jewels.  what is the difference between 23 vs 17 or so on?

 

Thanks in advance

bobbee's picture
bobbee
Posted May 2, 2012 - 11:25pm

The jewels are the small red or sometimes clear circles you see on the movement when you take the back off your watch. The various rotating cogs, wheels and ocillating levers run with their axles or pins seated into tiny holes called pivots.These are very lightly oiled for the pins to run easily. Most movements also have jewels on the pallets, which are the opposite end of the ocillating lever you may see moving back and forth next to the rotating balance wheel, (if you look using a loupe you can see the facinating movement of the escapement). All this means that the higher a jewel count, the better the movement. (usually)!

Hope this helps.

Reverend Rob's picture
Reverend Rob
Posted May 2, 2012 - 11:58pm

Panel Member

Usually is right. There was a period in the mid sixties when everyone was trying to outdo everyone else, and jewel counts soared to 100. (Orient and Waltham) Mostly these watches, showing more than 23 jewels, had jewels added to the plates in non-functioning capacities, merely to bump up the count. Jewels were sometimes added around the edge of the dial side of the plate, so the date disc could slide on them. This is entirely unnecessary, as there is very little friction at this point. Some watches had over 80 jewels around the plate under the rotor, which served no function. In cases like this, a high jewel count doesn't mean a better quality watch, and the major makers avoided this kind of misleading marketing for the most part. A fully jewelled watch has 17 jewels, cap jewels bump it up to 21 or 23. You can include jewels elsewhere, for example, Enicar was notable because they used a ruby pin as an axle for the minute wheel. It is functional, but hardly necessary. Higher jewel counts in automatic watches reflect additional jewels in the self winding system. The famous Buren micro rotor, which Bulova used in its 60's Ambassadors, could have as many as 30 jewels, and these are the ones collectors look for.  

A 7 jewel watch has only the escapement jewelled, and the rest of the train is metal on metal, pivots turning in metal bushings or simply holes drilled in the plates. These tend to wear like most clocks do, and re-bushing the watch is the only way to rejuvenate them once they wear and stop. 

bobbee's picture
bobbee
Posted May 3, 2012 - 12:03am

Hi Rob, ever come across old watches where the jewels have been removed by misinformed treasure hunters? Found a few myself!

Reverend Rob's picture
Reverend Rob
Posted May 3, 2012 - 9:00am

Panel Member

I have seen some with jewels missing, but this could also be because they were broken, and never replaced, or harvested by a watchmaker for another watch of the same calibre.

I have seen watches where the 'rubies' and 'sapphires' are listed separately. Rubies and Sapphires are the same thing chemically, and in the case of synthetic jewels, the colour is added. Since the jewels are synthetic, and have been since the late 1800's after Verneuil developed the blowpipe which bears his name, they aren't exactly precious gems. Even jewels prior to this would have been worth very little, it is not as if you could use them in jewellery or anything. Even diamond cap jewels, which are natural diamonds, and of poor quality and rough cut, are not especially valuable. 

As a side note, Natural Rubies were first used in watches by De Beaufré, after an invention in 1704 by Nicolas Fatio de Duiller, who designed a way to precision drill the stones. 

jass05
Posted May 3, 2012 - 8:21am

excellent responses, thank you both.

mybulova_admin
Posted May 4, 2012 - 5:47pm

Club 5000Panel Member

Just to confirm that those little red things in my watch are not in fact actual real rubies?

bobbee's picture
bobbee
Posted May 4, 2012 - 6:08pm

Nope,  made from aluminium oxide in crystalline form.