pencil" is cut to a hexagonal height of , but the outer diameter is slightly larger (about ) A standard, #2, hexagonal pencil is long. Biggest On 3 September 2007, Ashrita Furman unveiled his giant US$20,000 pencil – long, (with over for the graphite centre) – after three weeks of creation in August 2007 as a birthday gift for teacher Sri Chinmoy. It is longer than the pencil outside the Malaysia HQ of stationers Faber-Castell. By manufacture Mechanical Mechanical pencils use mechanical methods to push lead through a hole at the end. These can be divided into two groups: with propelling pencils an internal mechanism is employed to push the lead out from an internal compartment, while clutch pencils merely hold the lead in place (the lead is extended by releasing it and allowing some external force, usually gravity, to pull it out of the body). The erasers (sometimes replaced by a sharpener on pencils with larger lead sizes) are also removable (and thus replaceable), and usually cover a place to store replacement leads. Mechanical pencils are popular for their longevity and the fact that they may never need sharpening. Lead types are based on grade and size; with standard sizes being , , , , , , , , and (ISO 9175-1)—the size is available, but is not considered a standard ISO size. Pop a Point Pioneered by Taiwanese stationery manufacturer Bensia Pioneer Industrial Corporation in the early 1970s, Pop a Point Pencils are also known as Bensia Pencils, stackable pencils or non-sharpening pencils. It is a type of pencil where many short pencil tips are housed in a cartridge-style plastic holder. A blunt tip is removed by pulling it from the writing end of the body and re-inserting it into the open-ended bottom of the body, thereby pushing a new tip to the top. Plastic Invented by Harold Grossman for the Empire Pencil Company in 1967, plastic pencils were subsequently improved upon by Arthur D. Little for Empire from 1969 through the early 1970s; the plastic pencil was commercialised by Empire as the "EPCON" Pencil. These pencils were co-extruded, extruding a plasticised graphite mix within a wood-composite core. Other aspects By factory state: sharpened, unsharpened. By casing material: wood, paper, plastic. Health Residual graphite from a pencil stick is not poisonous, and graphite is harmless if consumed. Although lead has not been used for writing since antiquity, such