Sharpie paint pens are oil-based permanent markers that are AP-certified. For those who do not know, AP certification means the product does not contain any poisonous substances that can cause health issues. Also, their versatility of working on any surface makes them unique. You can use them on metal, pottery, wood, rubber, glass, plastic, stone, and more. If rock painting is in your mind, you can buy sharpie paints without any doubt.