Charcoal is excellent for drawing out splinters or other foreign bits under the skin. It can also be used on insect bites, bee stings, ingrown nails and blackheads. Lavender is wonderful for the skin and Tea Tree oil is an antiseptic. Apply a tiny bit to the spot and be sure to cover with a bandaid to prevent staining clothing.  Leave on at least overnight. May take up to a week to see results.