NNP

Strike Up, Struck Up.  To bring the surface relief of a numismatic or medallic item to its full intended height by striking in a press with proper dies and proper pressure –or the proper number of impressions (if a multiple-struck item). The pressman is responsible for every piece to be struck during his shift or production run and that they will be fully struck up with all detail intact.. He will frequently examine sample struck pieces (inspection) making sure the relief is as intended.

Press setup and running.  To begin a press run of a new coin or medal the pressman or pressroom foreman will SETUP the press, and strike a first specimen or two. This is a trial strike and is purposely at a lower impression than anticipated not to break a die during this stage (thus trial strikes are purposely weakly struck). He will increase the pressure until he feels it will be the proper amount to fully strike up the piece. These are the first strike specimens he will examine very closely.

The pressman looks for the following:  (1) every die cavity is filled, (2) all high points are intact, (3) there has been no die draw – metal flowing into then out of a die cavity – and (4) the dies are not misaligned. During the press run his sample inspections will always check the high points maintaining the relief is fully struck up. In addition he will check that no part of the die has broken, there are no hairline breaks, that the rims are intact and the dies have not rotated. He will use a magnifying glass for this inspection.

Multiple striking.  Medals that are multiple struck will always exhibit the state not struck up until the final blow. This is very evident in a process set. Only the final blow will have every cavity filled and high points intact (multiple blows are required to move the surface metal to fill every die cavity). Ideally the freshly struck finished piece, either coin or medal, should match the relief of the artist's original three-dimensional model, the galvano pattern or dieshell, though in miniature size.

                                                        

                     Not Struck Up                      

                                                         

       This oval medal is an excellent example of the   

  metal not filling every die cavity. The shadowy area  

  on the lower reverse is incuse on the medal's surface.

  Metal from the body of the blank did not completely    

  flow into and fill the obverse die's cavity.          

                                                        

       Note the congruent area on the obverse. The      

  shoulder is the high point on the obverse portrait,   

  the beard on the cheek is also a high point. These    

  two areas are not fully struck up on the reverse.     

  The force of the strike cause the metal to flow into  

  the obverse die cavities, but the metal had to come   

  form somewhere. In this case the nearest area was the 

  reverse surface.                                      

                                                        

       This medal exemplifies the concept important     

  to medallic artists: comgruent mass. Do not

  place two high relief areas back-to-back on a coin

  or medal design.                                               

                                                        

      For a multiple struck medal (which this is) the   

  problem is easily solved by softening the piece (by   

  annealing) placing it back in the press for another   

  blow or two. All multiple struck medals will exhibit  

  some form of not being fully struck up – until their 

  final blow.                                           

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