What are essential oils?

[Jyoti]

These are some interesting details I have found out about essential oils. Please add to the information so we know more and more about them. An essential oil is a concentrated liquid containing aroma compounds from plants. Oil is "essential" in the sense that it carries a distinctive scent, or essence, of the plant. Essential oils do not as groups need to have any specific chemical properties in common, beyond conveying common characteristic fragrances. I love the earthy smell of henna but am not keen on the medicinal smell of indigo. Some people don't like the smell of henna so adding a few drops of an essential oil like lavender or clove to the mixture makes your hair smell of whatever you fancy.
Most essential oils, such as lavender, peppermint, and eucalyptus, are distilled. Raw plant material, consisting of the flowers, leaves, wood, bark, roots, seeds, or peel, is put into an alembic (distillation apparatus) over water. As the water is heated the steam passes through the plant material, vapourizing the volatile compounds. The vapours flow through a coil where they condense back to liquid, which is then collected in the receiving vessel.
Historically, various essential oils have been used medicinally with applications ranging from skin treatments to remedies for cancer. Interest in essential oils has revived with the popularity of aromatherapy which claims that the specific aromas carried by essential oils have curative effects. Oils are diluted in carrier oil and used in massage, or burned as incense, for example.
Because of their concentrated nature, it is recommended that essential oils are not applied directly to the skin in their undiluted or "neat" form. Some can cause severe irritation, or provoke an allergic reaction. Instead, essential oils should be blended with vegetable-based "carrier" oil (a.k.a., a base, or "fixed" oil) before being applied. Common carrier oils include olive, almond, hazelnut and grape seed.

[HennaHelen]

Thank you for that informative Blog, Jyoti.

I agree, I enjoy the smell of henna but find that a few drops of lavender softens the smell a bit, mellows it - which is nice.
I also read somewhere (wikipedia, I think) that when you put certain essential oils (like lavender and tea tree oil) into your henna mix it actually helps to bring the dye out.

The power of scent is really amazing. Some scents help to make you feel relaxed and some can help you feel more alert. It's interesting how a smell can change your mood.