White Spots on Morgan Dollar

Comments

• AUandAG Posts: 24,946 ✭✭✭✭✭

  May 8, 2010 11:56AM

  dip residue prior to this toning?
  
  bob

  Registry: CC lowballs (boblindstrom), bobinvegas1989@yahoo.com
  

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• Meltdown Posts: 9,006 ✭✭✭✭✭

  May 8, 2010 11:57AM

  
  
  << <i>dip residue prior to this toning?
  
  bob >>
  
  
  Possibly, or just an honest contaminant of some sort.

  Click on this link to see my ebay listings.

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• 6Sigma Posts: 96 ✭✭

  May 8, 2010 12:00PM

  Am I correct that it has etched into the surface?

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• ricko Posts: 98,724 ✭✭✭✭✭

  May 8, 2010 11:34PM

  I have no idea what caused that.... although I would doubt it was dip residue.... too even and similar between the two spots. Very strange. Would like to be able to do an SEM scan of that... perhaps if you have access to a laboratory, someone will do it for you and identify the surface contaminants - could give a clue. Cheers, RickO

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• BAJJERFAN Posts: 31,402 ✭✭✭✭✭

  May 8, 2010 11:53PM

  It looks like it was held in some kind of device and there is contact/galvanic corrosion. It does look like raised donuts inside of the white area. Or it was held by a clamp long enough for the coin to tone around it.

  theknowitalltroll;

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• BAJJERFAN Posts: 31,402 ✭✭✭✭✭

  May 9, 2010 12:00AM

  
  
  << <i>I have no idea what caused that.... although I would doubt it was dip residue.... too even and similar between the two spots. Very strange. Would like to be able to do an SEM scan of that... perhaps if you have access to a laboratory, someone will do it for you and identify the surface contaminants - could give a clue. Cheers, RickO >>
  
  
  
  SEM would likely not be the best choice to determine the chemical makeup of the white areas; it is better suited to physical examination. I would opt for ESCA/XPS which can tell you the chemical composition of the surface contaminants. When I had it done here on a spotted silver eagle, his sample holder was too small to hold the whole coin so we had to cut it up. I wouldn't want to do that to this Morgan.

  theknowitalltroll;

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• BigE Posts: 6,949 ✭✭✭

  May 9, 2010 12:41AM

  Somebody applied a small amount of dip to the area to get rid of a spot. ------------BigE

  I'm glad I am a Tree

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• anablep Posts: 5,160 ✭✭✭✭✭

  May 9, 2010 1:44AM

  Frog eyes!!!

  Always looking for attractive rim toned Morgan and Peace dollars in PCGS or (older) ANA/ANACS holders!
  
  "Bongo hurtles along the rain soaked highway of life on underinflated bald retread tires."
  
  
  ~Wayne

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