The black part of your pencil is not lead. It is graphite. Graphite is a soft, dark mineral. People dig it out of the ground.

Graphite is soft and slippery. That makes it easy to write with. It is also used to help machine parts slide.

Long ago, people wrote with sticks of graphite. Later they wrapped the sticks in string or sheepskin. Later still, they set them in wood.

Today the core is graphite mixed with clay. More graphite makes a softer pencil. Its line is darker.

Makers cut thin boards of wood. They cut grooves along them. Many pencils are made of cedar. Cedar smells nice and does not warp.

Now comes the sandwich. Sticks of graphite lie in the grooves of one board. A second board goes on top with glue. Then the sandwich is cut into pencils.

Cedar is a good choice. You can sharpen it again and again. It does not splinter.

Pencils are painted or varnished. Makers coat them again and again until the color is right.

You can rub out a pencil mark. In the old days, people used lumps of bread. In 1770 a gum from trees was sold for rubbing out marks. It was called rubber.

Words to know

• graphite: soft black mineral
• cedar: tree wood
• rubber: tree gum
• sandwich: two slices