Weakly Struck. A piece produced in a press but not fully struck up, where features, devices or lettering appear indistinct. There are three causes of this: (1) too light a pressure as during press setup, (2) too thin a planchet or (3) too hard a planchett.. During setup particularly for a new coin design, the pressman will purposely start with too light a pressure and build up until the proper pressure will fully strike up a complete design. Light impressions on full weight planchets are a form of die trials.

A thin planchet in a coining press would cause a weakly struck piece because there is not enough metal to fill every die cavity and force metal against the collar. Thus too thin a planchet will appear weakly struck. Finally in multiple striking of art medals, a piece with the first several blows will appear weakly struck, but only requires additional blows to complete the design.

For too hard a planchet:. this was a common occurrence at the New Orleans Mint where the annealing equipment was unable to properly soften planchets if the production schedule was maintained. This was confirmed in 1900 by a detailed test and examination at New Orleans.