Over the weekend, I obtained a handful of pocket watches and two of them are rather nice (18 Size, 21J M1892 845 & 16 size M1899,19J Vanguard). In looking them over, I noticed one with a diamond cap jewel, so this got me thinking.....

What is the significance, if any, of a diamond cap jewel vs. one with an ordinary cap jewel? Is there a premium for a diamond cap jewel or is it only a nice little extra appreciated by the few?

For example, a 16 size, Vanguard, 19J, LS, 5 Pos., GJS, etc. (No. 161137302) w/diamond cap jewel. If the same Vanguard was made w/o the diamond is it less desirable - or about them same?

Best regards,

Greg

The diamond cap jewel was one of the advertised features of Waltham's better grade watches (American Watch Co., Riverside Maximus & Vanguard, as well as a few special order grades). As time passed these went the way of gold wheels and fine damasceening, and some of the later Vanguards do not have the diamond endstone. The diamond endstones represent an era of greater pride in workmanship. They look nice, but are also practical since a diamond cap jewel will not pit as even a sapphire cap can if the watch is run with dirty pivots.

I agree with Jerry. It was a one of several features used to distinguish the watch from the lesser grades and from the competitors product in the market place. It's one of the "quality" indicators.

For the collector it usually points to a higher quality watch, and in some makes/models can put it in the "fewer made" catagory.

Charlie

Good points, now that you mention it, my 1941 Vanguard does not have a diamond.

Did any other US watch maker use diamond cap jewels or only Waltham?

Both Elgin and Illinois used diamond endstones on some of their higher grade watches. These are the only American manufacturers that I can think of that used them, but there may be others.
The Gruen 50th Anniversary used them and they are sometimes found on Swiss and English verge, lever fusee and detent chronometer movements.