Unadulterated essential oils possess not only their active ingredients, but also secondary plant metabolites and trace compounds which aid in the healing properties. Different botantical regions offer different environmental conditions: soil, climate, altitude are among the factors that affect the plant and its metabolic constituents. Even the way the plant is harvested and distilled can affect the qualities of the oil.
These factors attribute to oils variations or “chemotypes.” Rosemary is a good example of the variety of chemical compositions. Rosemary has three types. Rosemary camphor is excellent for muscle cramps while Rosemary cineole type is suited for catarrhal (lots o' mucus) conditions and as a component in diffusor blends. Rosemary verbone's regenerating qualities make it indispensable for skin care.