Each essential oil blend listed contains only certified organic essential oils packaged in an amber glass bottle. The aromatherapy lockets include a Lava Rock and organic cotton on which to coat a couple of drops of your choice aromatherapy essential oil. The porous surface of the Lava Rock absorbs the oil, which emanates it's fragrance throughout the day. Other aromatherapy options: saturate and wring out a piece of an organic cotton ball or facial pad with essential oil or place a morsel of a favored essential oil soap inside the locket.