Graphite is a mineral found in marble, granite, and crystalline rocks, and is mined in Sri Lanka, Canada, the US, and Mexico. It is a mixture of carbon, iron, and silica, and contained in products such as batteries, polishes, lubricants, and also pencils – its name come from the Greek graphein, meaning to write. It was “proved” by Hannemann when he discovered the workmen were using black lead to heal cold sores. Homeopathically, graphite is ground to a powder to make the remedy and is used to treat skin complaints and metabolic imbalances.