Graphite drawing pencils are an art medium specially designed for drawing, as opposed to the writing pencils that are in common use. They are made with graphite, which is also called black lead or plumbago, mixed with clay. They come rated by hardness: the more clay mixed with the graphite, the harder the pencil; the more graphite, the softer. Many famous artists have sketched and drawn with graphite, along or with other media, including Ingres, Miró, Eakins, Cézanne, Delacroix, and Rodin.
There are two pencil-rating systems, a US one and a European one. The US system is numerical, while the European system, based on a lettering scheme, is the one generally used for artist’s pencils. The European rating system works like this: pencils are rated for hardness (H), blackness (B), and whether they have a fine point (F). The rating 9B is simultaneously the softest and darkest; 9H is both hardest and lightest. There are 20 ratings of graphite drawing pencils in the full range, though many manufacturers offer sets with a range of only 18, or selected pencils from within the entire range.
Sometimes, ranges of pencils are given the following names:
- Technical B to 9H Hard
- Designer 6B to 4H Medium
- Sketching 9B to H Soft
This fixed rating system has proved useful in other disciplines. Research laboratories use pencil hardness to test certain types of coatings in what is called the “Film Hardness-Pencil Test", also known as ASTM D 3363. This test uses the pencils 2B, B, HB, F, H, 2H, 3H, 4H, 5H, and 6H in an attempt to objectively rate the hardness of the film by testing for gouging and scratching. The test has been critiqued on the basis of both the variations in hardness between the same rated pencils produced by different manufacturers and change in pencil lead hardness over time.
Woodless graphite is a pencil-shaped drawing tool made only of the graphite/clay mix, with a thin paper wrapper. It is available in 9B, 8B, 6B, 4B, 2B and HB, and it can be used pencil-fashion or the wrapper may be removed to give a very broad drawing surface. Colored graphite pencils can be used in two ways: dry, they provide very subtle colors, but wet them, and the color becomes more vivid.
Graphite drawing pencils share techniques with other drawing media. Outlining, hatching, crosshatching, and stippling, for example, are all used. The wide range of leads and the possibility of mixing media — either other dry media, like charcoal and pastel, or wet media like ink wash and watercolor — extend the range of possibilities.
Among the accessories for this form of art media is the pencil lengthener, which is a device slipped onto the end of the pencil to make it easier to grip and allow the small tip to be used rather than thrown away. There are also pencil grips to decrease writing fatigue and caps to protect the lead. Erasers and sharpeners are also important materials. Vinyl erasers may prove most effective for erasing the range of graphite marks from a variety of surfaces.