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Activated charcoal is available at drug stores and natural health stores. It's commonly used as a remedy for indigestion, so it usually comes in the form of capsules. This pure black, all-natural substance is perfect for creating homemade eyeliner.  This is not the same as the type of charcoal you burn to cook food on the grill. Look for a jar of capsules labeled "activated charcoal" in the vitamin section of the store. If you can't find activated charcoal locally, it's available for purchase online. One bottle provides enough charcoal to make many year's worth of eyeliner. You can use an old eye shadow or lip balm pot, a tiny tin, or any other container you have on hand. Break the activated charcoal capsules into the container. You can use plain activated charcoal as eyeliner without mixing it with anything else. The charcoal will naturally mix with the oil on your skin to stay in place once you apply it. Dip your eyeliner brush into the container and apply eyeliner in your favorite style. If you like your eyeliner to have more of a paste or gel consistency, you can mix the activated charcoal with water or oil to make it a little damp. Start with just one or two drops, and keep mixing more in until your eyeliner reaches the consistency you want. Try mixing in one of the following ingredients:  Water Jojoba oil Almond oil Coconut oil Aloe vera gel

Summary:
Buy some activated charcoal. Break a few capsules into a small container. Dip your eyeliner brush into the charcoal. Experiment with different textures.