Japanese Twin

• Japanese Twin
  Otome Mine, Makioka-cho, Higashiyamanashi-gun, Yamanashi-ken, Japan
  
  This specimen consists of two pieces of quartz.
  The two pieces of quartz are combined under certain rule.
  As above figure, the angle made by crystal axes of two quartz is always 84°33’.
  In Meiji time, when this quartz had introduced widely in Europe, a German petrologist
  Goldschmidt named the specimen as Japanese Twin.