The simplest and most reliable of all marking instruments, the humble pencil has been with us since the pre-industrial age. A pencil’s essential ingredient, the part that leaves the marks, is graphite.

Graphite, like diamond and its close relative coal, is a form of pure carbon. Unlike the others though, it is an electrical conductor and so is used in things like lamps. It is also the most stable form of carbon at room temperature. Like diamond, it will burn but it does not ignite easily.

Back in the 1500s, when people first began finding and extracting graphite (farmers used it to mark sheep at one stage), the sciences of physics and chemistry had not yet reached their present sophistication and people thought graphite to be a form not of carbon but of lead. As a result, it was known as plumbago (Latin for “lead ore”). This is why we still refer to a pencil’s core as its “lead” despite the fact that it has nothing to do with the element, lead. The German word for pencil, Bleistift, literally translates as lead pen and this holds true in Arabic, Irish and several other languages as well. Bet you didn’t know that.

Because of its simple reliability and its tactile nature, the pencil has long been favoured by artists and writers. Mark Twain, for one, was never without a pencil and a notepad. He filled dozens of these pads with notes over the course of his life and roughly half of them are still in existence today. They are virtually priceless, as you would expect.

Here is a list of six more notable people who were dedicated to the use of pencils over the lengths of their working lives:

1. Thomas Edison (1847 – 1931), American inventor and businessman.

Edison was addicted to pencils and carried one with him wherever he went. Like a lot of pencil addicts, he developed very particular tastes over the years and eventually had his pencils made to his specifications by the Eagle Pencil company. Each Edison pencil was exactly three inches long, was slightly thicker than a standard pencil, and had softer graphite than was normally available.

2. Vladimir Nabokov (1899 – 1977), Russian-born multilingual novelist.

A documented oddball, the celebrated author of Lolita was fluent from his infancy in English, French and Russian but never learned to drive, type, or use a telephone. Everything he ever published though his varied and turbulent life was written and revised by him, usually several times, entirely in pencil.

3. John Steinbeck (1902 – 1968), American writer.

The Nobel Prize-winning author of twenty-seven books including the widely acclaimed Grapes of Wrath, Steinbeck was obsessive about several things and one of them was pencils. People who knew him claim that he used as many as sixty a day. His last major work and his own personal favourite was East of Eden, in the writing which he consumed more than three hundred pencils. His instrument of choice was the Eberhard Faber Blackwing 602.

4. Vincent van Gogh (1853 – 1890), Dutch post-Impressionist painter.

Surprising fact: one of the art world’s most beloved and tragic characters, van Gogh never started painting in oils until the final decade of his life. He drew with pencils, on the other hand, quickly and compulsively, from his childhood onward. His favourite pencils were made by the old German company Faber (Faber-Castell today) which he described as “superior to Carpenters’ pencils, a capital black and most agreeable”.

5. Johnny Carson (1925 – 2005), American television host and comedian.

The iconic host of The Tonight Show, despite his reserved demeanor, was always nervous on-camera and a celebrated fidgeter. To occupy his hands and keep them out of his pockets (he thought a man with his hands in his pockets looked like a slob) he formed the habit of playing with a pencil. Rather than risk stray marks or impaling anyone, he had his pencils made for him with an erasor at either end. Quirky, huh? And finally:

6. Roald Dahl (1916 – 1990), British writer.

Dahl, referred to as “one of the greatest storytellers for children of the 20th century”, was a man of firm tastes and convictions; he was offered an MBE in 1986 but refused it. According to his granddaughter he is buried with several of his cherished possessions and among these is a box of HB pencils. He wrote all his books in pencil, sharpening six as he began work every day and resharpening them only when all had become unusable.