Charcoal is made from vines, willow or other twigs that have been charred for use as drawing material. Charcoal is superb for blending and creating gradations of black. Sold mainly in pencil and stick form, charcoal is available in various grades from soft to hard. Vine charcoals are light and more easily erasable, but do not make a true black mark. Compressed charcoal makes thick heavy rich blacks. Although charcoal's main advantage is that it is blendable, this also means it can be smudged easily. The use of a fixative is necessary when work is complete.