essential oils are found in different parts of the plant:

flowering tops lavender.chamomile
grass lemongrass.palmarosa
leaves peppermint.cinnamon
peel lemon.bergamot.orange
seed cardamon.fennel
twig cypress.tea tree.eucalyptus
wood rosewood.cedarwood
gum frankincense

Because of their properties, essential oils are widely used in perfumes,
flavorings and medicines. The main methods are steam distillation, by compression, dissolving the oils out (extraction) or absorbing them, and by pressure and maceration (to separate into constituents by soaking). The methods used to extract the essential oil are time consuming and expensive and require a high degree of expertise. To maintain all of the therapeutic qualities, it must be extracted by steam distillation using extremely low pressure and low heat as not to defile the quality of the oil.

The name “essential” is derived from the Latin “quintessential”, meaning the fifth element. The fifth element was the vital element the alchemist sought to change base metals into gold. Each oil renders valuable health benefits when properly used in aromatherapy. Essential oils do not need to pass through the digestive system and can enter through the skin by massage oils, by various methods of inhalation, compresses or vaporizers. Essential oils interact with the body in three distinct ways: pharmacologically chemical change (through the blood stream), physiologically (effects the systems of the body) and psychologically (inhaled and a response is generated by the aroma). Given that it takes in excess of 220 pounds of rose petals to produce only 4 or 5 teaspoonfuls of oil, the chemical complexity and high concentration of essential oils makes every drop valuable and powerful.

Once you understand the principles of essential oils, you will want them in your life forever.
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