Graphite is bound in clay, and is available as sticks or as pencils, that are encased in wood. Graphite is graded according to softness. The hardest pencils are 8H and the softest are 9B. The softer the pencil the blacker the mark. Soft pencils are also easier to smudge. Hard pencils are best suited to accurate drawings that require sharp, crisp lines.

A Guide to Graphite