Synthetic Ruby Cups (Ø297 x 97 x T.177) Jewels Stones for Watches- MJ1155

1 x Ruby Cup (Image for illustrative purposes only).
Size Ø297 x 97 x T.177.
Stones or jewels were developed in watches to reduce friction at the points of heaviest wear. When metal rubs against metal and when oil breaks down, the damage to pivots and bearings can be rapid and devastating in terms of watch repairs. So in a nutshell, in order to reduction wear and friction between two pieces of metal that rub against one another, watchmakers use (today synthetic rubies) hard stones as friction points as they last a lot longer than metal.