Definizione

• Gold.  The heavy yellow precious metal, idolized by man for eons, ideal for coins and medals for the highest value and most desirable issues. Gold, as a metallic media along with bronze and silver, has been the composition of coins for 2800 years, the media for the most prized medals for 500 years, a bullion desired since antiquity and, only recently, collected as newly invented gold bullion coins and medals. The fascination of man for this yellow metal is timeless and continuing. It was natural that gold is used as a decoration, jewelry, adornment, in addition to a coinage metal, and the highest form of an award to man, the gold medal.
  Gold's appeal.  Ancient man and modern man both shared the desire to posses gold. No other metal, matter or material has so captivated the human mind. In addition to gold's universal appeal, it presents an aurora of desirableness, mysticism and materialism. Gold has always been a symbol of wealth, power, value, beauty, success, and the most acknowledged symbol of all: a medium of commerce and exchange. Gold is recognized world-wide and has been for thousands of years as the most noble of metals and the most accepted form of money.
          Outline of Entry:                 
      I. Definition and overview            
     II. Man's great love of yellow metal   
    III. Historical account                 
     IV. Gold Properties                    
         A. Weights and Measures            
         B. Gold colors.                     
      V. Gold Fineness                      
         A. Karat                           
         B. Gold standard                   
         C. Common gold alloys              
     VI. Coins & Medals in Gold             
         A. Gold coins.                      
         B. Gold recoining                  
         C. Gold medals                     
    VII. Marking                            
         A. Hallmarking                     
         B. Edgemarking                     
   VIII. Gold Imitations:                 
         A. Plating                         
         B. Rolled Gold                     
         C. Gold Tint                       
         D. Counterfeits                    
     IX. Testing, Assaying Gold             
         A. Assaying                        
         B. Touchstone                      
         C. Nitric acid                     
         D. Specific gravity                
  Gold Properties
  Most malleable of metals, easiest to strike.
  Fineness of gold expressed in carats of 24 parts purity, or as parts per 1000 (or per unit of 1) as .900 or 900 is
  Bob Julian:  Gold is normally refined to 0.999 purity and then alloy is added. Native gold is rarely used due to its indefinite proportion of metals and the presence of deleterious impurities such as lead and iron. A trace of iron in an ingot of otherwise pure gold will make the metal brittle and impossible to roll to a uniform thickness.
  Gold colors.  Gold in its purest form is always golden yellow. But very small
  amounts of other metals (as natural impurities or added as alloy) will change the color of yellow gold slightly. Silver or platinum will make a whiter gold; copper (as a common alloy) makes the gold somewhat reddish ranging from pink gold to red gold; the introduction of iron will turn the gold greenish; and the least known of all, natural impurties of bismuth will make a "black gold" (which cannot be duplicated artificially). See undercolor.
  Gold Fineness
  U.S. gold coins are 900 fine (alloyed with one-tenth copper), in England it is 916.7 fine (alloyed with 83.3 parts copper). In Australia gold is 916.7 fine, but is alloyed with 83.3 parts of silver; this is called Australian gold.
  Gold is abbreviated AU for Latin, aurum; AV or the AV ligature is used in numismatic cataloging (since, in English, AU is mostly used as abbreviation for the condition, About Uncirculated).
  "Metric gold" was used to strike U.S. $4 Stellas. Instead of alloyed completely with copper it contained a small amount of silver and 10 percent copper. See Breen p 510-11.
                                                  Marking
  "Tiffany law"– precious metal objects must be so marked passed 1904 in England, 1906 in the United States. This applies to all medals and medallic items (but, unfortunately, does not apply to the U.S. Mint which can manufacture gold and silver medals without such marking).
  Gold Imitations
  More numismatic items are called gold that really aren't because of many technologies, and man's foibles of wanting to fool his fellow man. Know what each term means. Some promotors are honest in their descriptions of their gold wannabees, others are not.
     Testing and Assaying Gold
  [MOR TO COM – MAJOR ARTICLE – ESTIMATED 80 LINES]
  Reference:                                                                                                                               
  B23 {1982} Kettell.

  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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