It is known as Orris Butter or Beurre d'Iris. It is produced by steam distillation of the rhizomes, which are washed and dried. They should be stored well protected against insect and fungus attack, for three years. The fresh rhizomes are almost odorless. Prior to distillation, the rhizomes are pulverized and distilled. The distilled oil solidifies in the receiver to a wax like, cream colored mass known as Orris Butter or Orris Concrete. It is solid because of its high content of myristic acid, a white, stearin like substance.