On March 30, 1858, Hymen Lipman received the first patent for attaching an eraser to the confine of a pencil. Personalized Pencils In 1862 Lipman sold his patent to Joseph Reckendorfer for $100,000, who went to sue the pencil manufacturer Faber for infringement. In 1875 the Matchless Court of the United States ruled against Reckendorfer declaring the patent invalid. The metal department is called a ferrule.
Manufacture
The diverse graphite pencil grades are achieved by altering the proportion of graphite to clay: the further clay the harder the pencil. Two pencils of the same grade but changed manufacturers will not necessarily make a mark of identical tone nor have the same hardness.