When the graphite deposit that produced the first pencils was discovered, the people thought it was lead. Later, chemists told them it was graphite, a form of carbon, but the 'lead pencil' had...
Pencils have never contained the metal, lead, although the word commonly used to describe the centre core of a pencil is, in English, 'lead'. The ancient tool which preceded the modern pencil was a...
The percentage is 0%. "Lead" in this case is a misnomer. Pencil "Lead" is made of graphite (an allotrope of carbon) and different levels of clay to control hardness.