Essential Oils come from plants, flowers or herbs. They are cold pressed, cold distilled or some combination of the two. In a few cases, they may be put in absolute ethanol, such as rose oil. The molecular structures of the components in the oils are small enough to penetrate the skin and olfactory system. They are generally used for their physicochemical and spiritual properties not their smell, however, their smells are often very pleasing as well.
Pure essential oils are very concentrated. In most cases, you do not want to put these oils directly on the skin but rather dilute them in a carrier oil or in something like bath salts. Do not ingest them. Due to their concentration, they can be very damaging to the digestive system. In addition, the acid in the stomach will break down the essential oils so that they don't enter the blood stream. It's best to either put them on the skin (in some form of carrier) or use them in a diffuser or spray. When using a diffuser, try and use a mist-based one as opposed to a heat-based one as the heat can break down the components of the essential oil.
Sprays are a very effective way to quickly and easily access the properties of essential oils. They can be used to freshen a room by providing a pleasing scent, to clear the energy of a space, or to help with concentration or connecting with your spirituality. Alternatively, you can add them to sea salt to make a wonderful bath salt.
Some commonly used oils are lavender, eucalyptus and frankincense. Here are some of the properties of these popular oils: