Pressed and natural charcoal sticks
The pressed charcoal sticks are made of charcoal, which has been enriched with additional pigment and then pressed together with clay to form crayons of different grades of hardness. It leaves strokes of deep black, which can be smudged with a finger to create an even area of intense black colour. Pressed charcoal is ideally suited to larger areas, as it is somewhat softer. Natural charcoal is harder, and thus perfect for drawing outlines and details.
Brush painting
Due to its high level of pigmentation, pressed charcoal can be painted over using a bristle brush and paraffin oil (baby oil or salad oil) to create areas of intense colour.
Transitions pressed charcoal
Pressed charcoal produces a very intense colour. Transitions enable its full range of shades, from pitch black to light grey, to be shown to best advantage.
Natural charcoal
Natural charcoal is made by charring willow twigs in the absence of oxygen. The strokes can be easily smudged with a finger to create a grey surface.
Corrections
Natural charcoal is available in a range of diameters. The colour deposit and character of the charcoal sticks is uniform. The strokes are very easy to erase. Fixing is required to preserve the drawings.
Transitions natural charcoal
Natural charcoal has a very limited intensity of colour. Its delicate greyish-blue hue is shown to advantage in very fine colour transitions.
Fixing
Charcoal drawings smudge very easily, and thus require fixing.