Charcoal and pencil are superb for portrait subjects where a high level of detail is required. Each medium may be used on its own, or in combination, depending on the levels of contrast required in the drawing.
Charcoal and pencil perform similarly, but pencil produces shades of grey, while charcoal delivers shades of black.
I favour pencil for a soft and delicate image, and charcoal for high contrast subjects, but usually combine the two to achieve a broader spectrum of tones.
I normally draw on smooth white cartridge paper, but switch to coloured paper to allow white chalk highlights to be added, and further increase tonal contrast.
