Most pencil cores are made of graphite powder mixed with a clay binder. Graphite pencils (traditionally known as "lead pencils") produce grey or black marks that are easily erased, but otherwise resistant to moisture, most chemicals, ultraviolet radiation and natural aging. Other types of pencil cores, such as those of charcoal, are mainly used for drawing and sketching. Coloured pencils are sometimes used by teachers or editors to correct submitted texts, but are typically regarded as art supplies, especially those with cores made from wax-based binders that tend to smear when erasers are applied to them. Grease pencils have a softer, oily core that can leave marks on smooth surfaces such as glass or porcelain.

The most common pencil casing is thin wood, usually hexagonal in section but sometimes cylindrical or triangular, permanently bonded to the core. Casings may be of other materials, such as plastic or paper. To use the pencil, the casing must be carved or peeled off to expose the working end of the core as a sharp point. Mechanical pencils have more elaborate casings which are not bonded to the core; instead, they support separate, mobile pigment cores that can be extended or retracted (usually through the casing's tip) as needed. These casings can be reloaded with new cores (usually graphite) as the previous ones are exhausted.


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Pencil, from Old French pincel, from Latin penicillus a "little tail" (see penis; pincellus is Latin from the post-classical period[1]) originally referred to an artist's fine brush of camel hair, also used for writing before modern lead or chalk pencils.[2]

As a technique for drawing, the closest predecessor to the pencil was silverpoint or leadpoint until in 1565 (some sources say as early as 1500), a large deposit of graphite was discovered on the approach to Grey Knotts from the hamlet of Seathwaite in Borrowdale parish, Cumbria, England.[4][5][6][7] This particular deposit of graphite was extremely pure and solid, and it could easily be sawn into sticks. It remains the only large-scale deposit of graphite ever found in this solid form.[8] Chemistry was in its infancy and the substance was thought to be a form of lead. Consequently, it was called plumbago (Latin for "lead ore").[9][10] Because the pencil core is still referred to as "lead", or "a lead", many people have the misconception that the graphite in the pencil is lead,[11] and the black core of pencils is still referred to as lead, even though it never contained the element lead.[12][13][14][15][16] The words for pencil in German (Bleistift), Irish (peann luaidhe), Arabic (  qalam ra), and some other languages literally mean lead pen.

The usefulness of graphite for pencils was discovered as well, but graphite for pencils had to be smuggled. Because graphite is soft, it requires some form of encasement. Graphite sticks were initially wrapped in string or sheepskin for stability. England would enjoy a monopoly on the production of pencils until a method of reconstituting the graphite powder was found in 1662 in Germany. However, the distinctively square English pencils continued to be made with sticks cut from natural graphite into the 1860s. The town of Keswick, near the original findings of block graphite, still manufactures pencils, the factory also being the location of the Derwent Pencil Museum.[17] The meaning of "graphite writing implement" apparently evolved late in the 16th century.[18]

In England, pencils continued to be made from whole sawn graphite. Henry Bessemer's first successful invention (1838) was a method of compressing graphite powder into solid graphite thus allowing the waste from sawing to be reused.[25]

American colonists imported pencils from Europe until after the American Revolution. Benjamin Franklin advertised pencils for sale in his Pennsylvania Gazette in 1729, and George Washington used a three inches (7.5 cm) pencil when he surveyed the Ohio Country in 1762.[26][better source needed] William Munroe, a cabinetmaker in Concord, Massachusetts, made the first American wood pencils in 1812. This was not the only pencil-making occurring in Concord. According to Henry Petroski, transcendentalist philosopher Henry David Thoreau discovered how to make a good pencil out of inferior graphite using clay as the binder; this invention was prompted by his father's pencil factory in Concord, which employed graphite found in New Hampshire in 1821 by Charles Dunbar.[7]

Munroe's method of making pencils was painstakingly slow, and in the neighbouring town of Acton, a pencil mill owner named Ebenezer Wood set out to automate the process at his own pencil mill located at Nashoba Brook. He used the first circular saw in pencil production. He constructed the first of the hexagon- and octagon-shaped wooden casings. Ebenezer did not patent his invention and shared his techniques with anyone. One of those was Eberhard Faber, which built a factory in New York and became the leader in pencil production.[27]

Joseph Dixon, an inventor and entrepreneur involved with the Tantiusques graphite mine in Sturbridge, Massachusetts, developed a means to mass-produce pencils. By 1870, The Joseph Dixon Crucible Company was the world's largest dealer and consumer of graphite and later became the contemporary Dixon Ticonderoga pencil and art supplies company.[28][29]

By the end of the 19th century, over 240,000 pencils were used each day in the US. The favoured timber for pencils was Red Cedar as it was aromatic and did not splinter when sharpened. In the early 20th century supplies of Red Cedar were dwindling so that pencil manufacturers were forced to recycle the wood from cedar fences and barns to maintain supply.

It was soon discovered that incense cedar, when dyed and perfumed to resemble Red Cedar, was a suitable alternative. Most pencils today are made from this timber, which is grown in managed forests. Over 14 billion pencils are manufactured worldwide annually.[31] Less popular alternatives to cedar include basswood and alder.[30]

On March 30, 1858, Hymen Lipman received the first patent for attaching an eraser to the end of a pencil.[35] In 1862, Lipman sold his patent to Joseph Reckendorfer for $100,000, who went on to sue pencil manufacturer Faber-Castell for infringement.[36] In Reckendorfer v. Faber (1875), the Supreme Court of the United States ruled against Reckendorfer, declaring the patent invalid.[37]

Historian Henry Petroski notes that while ever more efficient means of mass production of pencils has driven the replacement cost of a pencil down, before this people would continue to use even the stub of a pencil. For those who did not feel comfortable using a stub, pencil extenders were sold. These devices function something like a porte-crayon...the pencil stub can be inserted into the end of a shaft...Extenders were especially common among engineers and draftsmen, whose favorite pencils were priced dearly. The use of an extender also has the advantage that the pencil does not appreciably change its heft as it wears down."[30] Artists use extenders to maximize the use of their colored pencils.

Graphite pencils are the most common types of pencil, and are encased in wood. They are made of a mixture of clay and graphite and their darkness varies from light grey to black. Their composition allows for the smoothest strokes.

Solid graphite pencils are solid sticks of graphite and clay composite (as found in a 'graphite pencil'), about the diameter of a common pencil, which have no casing other than a wrapper or label. They are often called "woodless" pencils. They are used primarily for art purposes as the lack of casing allows for covering larger spaces more easily, creating different effects, and providing greater economy as the entirety of the pencil is used. They are available in the same darkness range as wood-encased graphite pencils.

Liquid graphite pencils are pencils that write like pens. The technology was first invented in 1955 by Scripto and Parker Pens. Scripto's liquid graphite formula came out about three months before Parker's liquid lead formula. To avoid a lengthy patent fight the two companies agreed to share their formulas.[38]

Charcoal pencils are made of charcoal and provide fuller blacks than graphite pencils, but tend to smudge easily and are more abrasive than graphite. Sepia-toned and white pencils are also available for duotone techniques.

Carbon pencils are generally made of a mixture of clay and lamp black, but are sometimes blended with charcoal or graphite depending on the darkness and manufacturer. They produce a fuller black than graphite pencils, are smoother than charcoal, and have minimal dust and smudging. They also blend very well, much like charcoal.

Grease pencils can write on virtually any surface (including glass, plastic, metal and photographs). The most commonly found grease pencils are encased in paper (Berol and Sanford Peel-off), but they can also be encased in wood (Staedtler Omnichrom).[39]

Watercolor pencils are designed for use with watercolor techniques. Their cores can be diluted by water. The pencils can be used by themselves for sharp, bold lines. Strokes made by the pencil can also be saturated with water and spread with brushes.[39]

Carpenter's pencils are pencils that have two main properties: their shape prevents them from rolling, and their graphite is strong.[40] The oldest surviving pencil is a German carpenter's pencil dating from the 17th Century and now in the Faber-Castell collection.[41][42]

Copying pencils (or indelible pencils) are graphite pencils with an added dye that creates an indelible mark. They were invented in the late 19th century for press copying and as a practical substitute for fountain pens. Their markings are often visually indistinguishable from those of standard graphite pencils, but when moistened their markings dissolve into a coloured ink, which is then pressed into another piece of paper. They were widely used until the mid-20th century when ball pens slowly replaced them. In Italy their use is still mandated by law for voting paper ballots in elections and referendums.[43] e24fc04721

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