In 1960 we attained the domestic
manufacture for Watch Jewels for the first time in Japan.
Watch Jewels are mainly made from Ruby Material. The Ruby
is hard to grind and has a highly wear resistance. However,
the Ruby Chips grind easily because it is a single crystal.
The grinding and polishing of Ruby was very difficult.
Artificial Rubies are also used for Watch Jewels. The inscription
of “17 J” or “17 Jewel” on a watch dial is an indication of
the jewel number in the watch.
Balance is the most important feature in the watch for ticking.
The Roller Jewel is on the Large Balance Wheel that swings
back and forth. It engages with the Pallet Fork on the end
opposite of the Pallet Jewels. The balance wheel can swing
five to six times per second.
