When buying jewels, which balance jewel is the upper, and which is the lower one ?

I think lower balance jewels are the ones on the pillar plate. The upper jewels are on the bridge side.

Tim.

Tim is correct upper is the one in the balance cock on some watches the upper and lower balance jewels are the same..

Thanks!

Donald, I don't know how much experience you have in replacing balance jewels, I know I only have experience limited to Waltham Pocket watches 12S to 18S. The points I found you need to observe are:

1. the hole size in the jewels match the pivot size of the staff. Usually 0.01-0.02 larger in the jewel. I test fit the jewels on the staff pivots before I fit them to the cock or foot as sometimes they don't always arrive as ordered & you can spend a lot of time chasing a staff binding in a smaller than ideal hole that wasn't part of the original problem.

2. you need to match the thickness of the original jewel (if in a setting) being replaced. If you get a jewel that is close you can "adjust" the cock via various means to get the correct amount of end shake on the staff. If you've replaced the staff as part of the repair, you'll have to check/adjust the endshake in any case.

Hope this helps.

Regards, Phil