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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
malpais
  • The ragged surface of a lava-flow.
'Malpais' translates from Spanish as 'bad land.'