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No higher resolution available.Cobalt_OreUSGOV.jpg (600 × 450 pixels, file size: 79 KB, MIME type: image/jpeg)
 
      
       
       
       
        
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         This is a file from the  Wikimedia Commons. The description on its  description page there is shown below.Commons is a freely licensed media file repository.  You can help. 
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        Cobalt ore
        
         
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            This image has currency in it to indicate scale. Avoid using objects such as coins for scale, as they will require people unfamiliar with them to look up the dimensions or guess, both of which defeat the purpose of the object in the first place. Coins are particularly bad as they can reinforce a geographical bias, and some coins' designs are  not free content. Ideally, a photograph should include a  ruler with the subject (as seen in  this photo) or add a scale marking via an image editor instead (as seen in  this photo).  SI/metric units are the most commonly used worldwide (see  metre,  1 E-2 m). Examples of bad practice:  here.  | 
          
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        Common coin diameters for reference:
        
        
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 Source:  http://resourcescommittee.house.gov/subcommittees/emr/usgsweb/photogallery/ ; English Wikipedia, original upload 3 August 2004 by  Chris 73
        
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         This image is a work of the "Minerals in Your World" project, a cooperative effort between the  United States Geological Survey and the  Mineral Information Institute. The images were featured in the "Minerals and Materials Photo Gallery" on the website of the  U.S House Subcommittee on Energy and Natural Resources. As a  work of the  U.S. federal government, the image is in the  public domain. | 
         
          
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        Date/Time | 
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        05:45, 14 September 2005 | 
        600×450 (79 KB) | 
        Saperaud | 
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