Natural charcoal sticks are the oldest sketching and drawing material in the world. Their greyish-blue hue has always held a fascination for artists, even the Old Masters. A combination of compressed charcoal, soot, and clay give Faber-Castell Pitt Monochrome Wax-Free Charcoal Pencils their deep black color. They glide softly across the paper, rub and smudge easily, and can be repeatedly overlaid. Their rich black lines can also be erased easily. Available in three degrees of hardness — soft, medium and hard.