Essential oils contain highly concentrated and scented vegetable extracts. Essential oils are derived from various plants by extracting method. Steam distillation is the normal method by which essential oils are derived from vegetative matter. Extracted essential oils are transparent and clear oils but some are colored. Essential oils which are extracted from lemon, orange, tangerine, patchouli and lemongrass are yellow in color. These oils are concentrated, volatile, and usually stored in a small bottle. They easily evaporate, leaving no residue and should be kept tightly closed.

Essential oils are grouped by their lightness and are classified into top, average and base oils. The top oils evaporate rapidly due to their lightness and should be handle with care when storing them. Base oils evaporate the least rapidly. Oils mixes that are the most stable and balanced are those that consist of oils from all three categories top, average and base.

Notice that essential oils are always sold in tinted glass bottles to protect them from light. Sun light (UV) and high temperatures are the main enemies of essential oils. Amber glass bottles offer good protection from UV. Essential Oil containers are best kept in a dark, cool place with temperature fluctuations kept to a minimum. Be careful to keep the lids tightly, otherwise your oils will evaporate into thin air. Essential Oils are best stored in amber glass bottles with a tight lid. Under good conditions essential oils can be stored for periods of 6 months to several years. Some oils like myrrh, sandalwood, frankincense and patchouli will even improve or "mature" with age, very similar to a good wine.

Many essential oils are flammable and/or act as strong solvents. Eucalyptus oil for example can be used to remove glue from old stickers or to strip paint. Avoid contact of essential oils with the skin as they can cause irritation. Using latex gloves and wearing protective glasses is recommended when handling essential oils. Use caution when using essential oils. Concentrated essential oils are too strong to be applied directly on the skin. Carrier oils are used when thinning essential oils for massage. Try not to use essential oils on sensitive areas such as the eyes. For application to the skin, dilute the essential oil with a good quality carrier oil e.g. jojoba, almond or olive oil. 3% essential oil with 97% carrier oil is a safe ratio.

There are two ways in which essential oils work; psychologically - by way of the body's sense of smell on the central nervous system by vaporizers or smelling of the oils; and physically - through the skin by mixing the oils for massage, foot baths or steam inhalation.