Definition

• Repair and Restoration.  If a medallic item is not too severely damaged it can be reworked and brought back to an acceptable state or condition. Physical damage – scratches, dents, nicks, pitting, blisters, fire damage, graffiti – can be restored usually by chasing. Chemical damage – tarnish, diffusion, stains, blotches, inexpert cleaning, fugitive patinas – can be restored by refinishing. Provided in all instances, of course, any damage on the piece to be treated is not already deteriorated beyond repair. Large edge nicks, generally, cannot be repaired. Where a similar size nick in a field can be easily repaired by chasing (metal is drawn from surrounding surface to fill the depressed area).
  What should be restored?  Coins, other than plugging a hole, cannot be restored.
  Perhaps this is proper. The intent of their makers was to strike a coin without finish to circulate as a medium of exchange where abrasion due to wear is a natural proceeding. Medals on the other hand, were not intended to circulate or wear. The intent of their makers was to create an attractive art object, to remain pristine, often with an attractive finish, to last for a long time.
  Restoring actually changes condition. A coin's condition should not be upgraded once it has worn – that was its purpose. But in the vicissitudes of time that affects all objects, medals darken or tone, they may be dropped, or other objects dropped on them. This was not how their creators intended them to exist; they can and should be upgraded or restored to the pristine condition their creators intended. Therefore, the only rule of restoring and refinishing a medal is not the propriety of doing so, but that the cost is justified:  the piece itself is valuable enough to warrant the cost of the restoration work.
  Restoring medals.  Impaired medallic items are restored by a number of steps. These include:  (1) delacquer and clean; stripping off, removing all lacquer and dirt and degreasing where necessary; (2) reverse plating; removing any plated metal if present; (3) determining the base metal (the experienced chaser can do this by observing color and testing hardness), and by determining what can and cannot be done in any restoration work; (4) repairing by plugging offensive holes, if any; (5) chasing work, the smoothing of dents, nicks or scratches, removal of unwanted graffiti; (6) other work on the base metal such as inscribing, removal or adding loops and replating; (7) refinishing in all of its processing including relacquering; and finally, (8) remounting if necessary, replacing ribbon, links, jump rings, chains for suspension or whatever.
  Restoring dies.  Some restoration work can be done on dies. Old dies generally
  need attention to remove rust and corrosion by chasing – smoothing out rust pits are possible. Chasing is usually done after the die is annealed to soft state (but can be done at any hardness). Also worn or filled lettering can be recut or re-engraved to sharpen up worn areas; rough areas can be burnished. Old dies are often found in brittle state; they are tested for hardness. Then the die is tempered – heat treated – to withstand the pressure of striking. In all this action to improve the die, however, one thing cannot be done – once a die starts to sink, nothing can be done to repair this damage and the sinking will continue during any continued striking.
                                                            
                           Don't Do It Yourself                    
                                                            
       In all restoration work experience and knowledge –  
   of alloys, metalworking, patinas, finishing, chasing –  
   is critical. This is not an area for the amateur or the  
   inexperienced. Inexperienced repair work looks worse     
   than the original damage. Have a professional do it!     

  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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