The pencil “lead” is actually a mixture of graphite and clay. More clay in the mixture makes the lead harder. A harder lead has a higher number. Pencils are numbered from 1-3 but most people use a ...

The whole point of a mechanical pencil is to have perfect sharpness forever. Yet without precise engineering and build quality, the standard slender leads are doomed to constant breakages. This ...

What is the difference between mechanical and clutch pencils? When you click a mechanical pencil, a predetermined amount of ...

No.2 pencils are widely used, but you may not know what the number actually refers to. This video explains how pencils developed into their modern form and the significance of the labeled numbers.