It is recommended that essential oils are only placed directly on the skin if mixed and diluted with a carrier oil such as sweet almond oil or apricot kernel oil.   Our lava stone spinner has a metal back so the lava stone is not directly touching your skin when worn as a ring. If you fidget with the ring frequently (and, thus, touch the lava stone often) you may wish to dilute your essential oil before adding a drop to your lava stone. Additionally, if you wear the lava stone spinner in a necklace base where the pendant is touching your skin, you may also wish to dilute your essential oils with a carrier oil since the spinner can rotate.