Definition

• Box Medal, Box Thaler.  A medal or large coin machined in such a way that it has a hollowed center – or one made of two sides with a hollow inside – made to open up to reveal the inside chamber much like a locket. Great ingenuity was employed to affix the obverse and reverse halves, either by unseen hinge or screw threads; thus knowledge of the hidden release was necessary to open the object. Inside was found drawings or engravings on thin disks, called roundels: these were made of paper, mica, cloth, porcelain, ivory or other very thin media. Some roundels were in color and some where in multiple views, printed and folded in accordion fold, then cut to fit inside the chamber.
  Box thalers were first made in early 16th century in Augusburg and Nuremberg Germany (schraubthaler), later in Austria and other parts of the world. Large trade coins or medals were especially selected to be made into box items because of their size.
  A numismatic object with a perceptible light weight – often the only diagnostic to indicate the object was indeed a box medal – because the inside chamber would reduce the total weight. Opening the object may not be easy until the hidden release is discovered.
                  How to find the hidden
                   release in a box medal.  
   
              Where to press to open a suspected box
   medal? Start at the two obvious places first – the
   12 o'clock and 6 o'clock positions (most often
    where the concealed hinge would be located).  
    Apply pressure with the tip of your finger on the
    surface near the rim of the piece. If not, try other
    locations. You may be surprised it opens up!
    Another type unscrews: press obverse and
    reverse in rotating opposite directions. 
  An early British example is the Peace of Paris Box Medal of 1763; it was unusual in that it contained 60 circular disks illustrating events in the Seven Years War, 1756-63 (Brown 89).
  A later development was the manufactured box medals (as for World's Fairs) in imitation of those hollowed out from coins and medals. The two sides – called plates – were diestruck shells both with rims attached to form the edge. One side has a skirt to form the outer edge. The other side has a slip, which fits inside the skirt. These were quite popular at the World's Fair Exposition, Chicago, 1892-3.
  An innovative box medal was created for the 1904 Saint Louis World's Fair. Only a portion of the medal opens up to reveal a fixed photo inside. In addition, this piece also was enameled (Krueger 260).
  There is a thin line between medallic box items and jewelry lockets. Both have sides (plates) that open up, and both reveal an inside chamber in which a photo, print or other thin items (roundels) can be seen. Jewelry lockets are more obvious in the hinge, usually found on the outside to indicate its inside treasure. Medallic box items are more subtle, the hinge or screw is hidden.
  Numismatic writer Walter Breen states that jewelers made box dollar lockets from United States trade dollars because of their questionable legal status. These trade dollars had not circulated in China and did not bear chop marks, but were altered with impunity from U.S. laws that prohibited vandalizing current U.S. coins.
  In World War II, however, hollowed out coins were employed by spies to pass microfilm from one to another. These were, in effect, "box thalers."
                        Box Medal Terms                    
                                                           
        Several terms are employed by numismatists to      
   describe box medals, box thalers and their terminology: 
                                                            
        Hidden release – where to press to open the object.
                                                           
        Concealed hinge – connecting the two halves inside
   the object.                                              
                                                           
        Screw threads – where the halves have screw threads
   to hold the two separate, which screw back together.    
                                                           
        Chamber – the hidden compartment inside the box   
   medal, the area available for inserting the roundels.   
                                                           
        Machined – a solid coin or medal hollowed out by  
   cutting in half and removing inside metal by careful    
   routing.
                                                 
        Plate – a single side: the obverse plate or the   
   reverse plate.                                          
                                                                                                                     
        Shell – diestruck thin plates of metal, usually   
   white metal, tin, iron or brass.                        
                                                           
        Skirt – the outside rim that forms the edge of    
   the medal attached to one of the plates.                   
                                                        
        Slip – the inside rim attached to the opposite    
   plate; the slip goes inside the skirt.                  
                                                           
        Roundel – one or more inserts placed inside a box 
   medal; made of paper, mica, cloth, porcelain, ivory or  
   other thin media.                                        
                                                           
        Accordion fold – a printed piece with alternating 
   folds like an accordion bellows.                        
                                                           
        Diecut – after the roundels are printed and folded
   it is cut out to fit within the chamber.                
  References:                                                                                                         
  NC10 {1988} Breen p 467.

  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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