Définition

• Planchet.  A round metal disk (or other shape) made for striking into a coin or medal. The term blank is widely used in the metalworking field. Planchet is only used for coins and medals. Likewise, the word flan is French for a coin or medal blank. A planchet is the end product of the rolling and BLANKING operation. It produces a piece of metal of the proper composition, weight, thickness (and diameter if round). Further to make a blank into a planchet requires treatment of the edge[RWB1] .
  The blanking process, formerly called cutting and cutting-out (particularly in England), leaves a burr on the exit side of the blank. The piece must be deburred. This, plus additional preparatory steps, occur by upsetting  in an upsetting mill (British terms “rimming” and “rimmer”) which thickens the edge, makes the piece perfectly round, in addition to deburring. Since this step work hardens the blank, it must be annealed (or softened), then riddked (to eliminate imperfect blanks) and metal cleaned (to remove all surface contaminants). At this stage the planchet is ready to be fed into the press. All of these steps are required to create perfect blanks for automatic feeding into coining presses (if not they would cause mis-strikes and could jam the press).  See blank, blanked, blanking.
  A blank planchet is a planchet that has not been struck. If it has not been upset, collectors call this a type one blank, and after it is upset, type two planchet. A better terminology for these two stages would be "blank" for type one, and "press ready planchet" for type two.
   

  excerpted with permission from

  An Encyclopedia of Coin and Medal Technology

  For Artists, Makers, Collectors and Curators

  COMPILED AND WRITTEN BY D. WAYNE JOHNSON

  Roger W. Burdette, Editor

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