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Graphite Reference Libraries

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Pencil
2010-09-16 16:05:54

A pencil, containing a solid pigment core within a protective casing, is a common writing implement or art medium. Having a case keeps the pigment from breaking as well as from marking the user's hand. Pencils differ from pens because they leave marks by physical abrasion rather than staining the paper. The pigment leaves behind a trail of material that adheres to the sheet of paper or other...

Graphite
2005-05-26 10:49:47

Graphite (named by Abraham Gottlob Werner in 1789, from the Greek γραφειν: "to draw/write", for its use in pencils) is one of the allotropes of carbon. Unlike diamond, graphite is a conductor, and can be used, for instance, as the material in the electrodes of an electrical arc lamp. Occurrence Associated minerals include: quartz, calcite, micas, iron meteorites and...

Word of the Day
tesla
  • The unit of magnetic flux density in the International System of Units, equal to the magnitude of the magnetic field vector necessary to produce a force of one newton on a charge of one coulomb moving perpendicular to the direction of the magnetic field vector with a velocity of one meter per second. It is equivalent to one weber per square meter.
This word is named for Nikola Tesla, the inventor, engineer, and futurist.