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.
We established a highly precision processing technology overcoming the difficult problems to make a 10um hole in a small ruby and polish. Our "highly precision processing technology" which enables mass production of these products with maintaining a high accuracy was started from the first manufacture of Watch Jewels.