Idyllism

Steam Distilled: The vast majority of true essential oils are produced by steam distillation. Water is heated to produce steam and is piped into the distillation unit, usually at high pressure. The steam passes through the plant material, and exits into the condenser. The Essential Oil will normally float on top of the Hydrosol (the distilled water component) and is then separated off.

Cold Pressed: This method is mainly used in extracting oil from citrus peels. Machines which score the rind and press down on on the peel capture the resulting oil. Although many citrus oils are also produced by steam distillation, they seem to lack the vibrancy of the cold pressed oils.

Sovent Extracted: A 1% solvent is used to extract the oil, e.g. Benzoin.  This type of essential oil is only 99% pure, though still therapeutic and able to be used in massage blends and in the bath.