Milkspotting on Perth Mint 2015 kilo Kookaburra

Discussion in 'Silver Coins' started by SpacePete, Dec 14, 2014.

  1. yrh0413

    yrh0413 New Member

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    that is one AWESOME post from Perth Mint! :D You're da man!
     
  2. barsenault

    barsenault Well-Known Member

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    Indeed, thanks Ron and Bron. Appreciate the transparency. This is helpful info. Fingers crossed that you can pinpoint the problem and fix it once for all. Thanks much. Bob A
     
  3. silvertongue

    silvertongue Member Silver Stacker

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    Hmm... if the problem stems from AgCl inclusions, maybe a quick electrolysis in a weak solution of sodium carbonate and dextrose may remove?
    I need to buy some milk-spotted maples and try this...
     
  4. badhop55

    badhop55 New Member

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    Damn! I have a proof kilo Dragon that was pristine when I locked it up over a year ago.

    Positive thoughts.

    Positive thoughts.

    Thanks, Ron for the candid, up front post.
     
  5. Gatito Bandito

    Gatito Bandito Active Member

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    I can see how the microscopic particles might be causing some of the small spotty milk-spots..

    But how are the large areas of milk-*splotches* explained? A concentrated boatload of particles in that area?


    See the area below the queen's neck, down to the edge of the coin & traveling to "8 DOLLARS," for example..

    [​IMG]
     
  6. Ronnie 666

    Ronnie 666 Well-Known Member Silver Stacker

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    Logically for silver chloride to appear this must be related to exposure to Cl- ions. I believe the blanks have an acid wash ? is that acid HCl, if so that will produce AgCl. Also tap water contains Cl- ions from chlorination. It is logical that exposure to tap water or HCl is the cause. The dust may act as a nidus for precipitation but it is probably not the cause.
    Just my take ?
     
  7. Gatito Bandito

    Gatito Bandito Active Member

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    That's what I'm thinking.

    I have a 10-oz PAMP Fortuna -- which I willingly kept instead of exchanging it, as I think it looks sort of neat like this -- which has those large milk-splotches on the sides, similar to the above photo. And in the middle of those splotches are somebody's milky fingerprints, as if either the bar and/or their hands were wet with liquid at the time.

    Though since the worker obviously had bare hands, I'm going to rule out any kind of acid, at least in this case.

    Wish I had I good camera so I could post a photo here.
     
  8. barsenault

    barsenault Well-Known Member

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    dude seriously? you can't take a snap shot of the spots, because you can't get a good photo, yet you're buying hunks of metal, like Lunar goats. LOL.
     
  9. Gatito Bandito

    Gatito Bandito Active Member

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    Seriously.

    Money spent on a new camera means less of the shiny stuff for me.


    Priorities.. :D
     
  10. SpacePete

    SpacePete Well-Known Member Silver Stacker

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    I agree with your priorities :)
     
  11. iceblue

    iceblue Well-Known Member

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    We found the MORE ultra sonic cleaning was done (acid wash) The more the milkspotting occurred. We also left a round out of the capsule exposed to air, while it did tone, it did not develop milkspots. Ronnie I would say you are pretty close to the mark there.
     
  12. barsenault

    barsenault Well-Known Member

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    wow. hopefully Ron Currie is paying attention to this thread. :)
     
  13. barsenault

    barsenault Well-Known Member

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    I do too...I always think of ounces spent when I buy anything. LOL. Drives the wife crazy. LOL.
     
  14. Pirocco

    Pirocco Well-Known Member

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    It all looks like such scenario. It's a growth of AgCl crystals around some surface deposit. The latter isn't like some 'infection', just the trigger to make the growth start, much similar to a snowflake where the presence of any particle/dust serves as the core to make the crystal start to develop.
    But in the snowflake's case it doesn't need further particles, just more water and low temperature.
    While in this topics case, the growing itself needs Cl atoms (since the blemish is AgCl), so in order to grow, a (further) supply / presence of Cl is required.
     
  15. SpacePete

    SpacePete Well-Known Member Silver Stacker

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    The spotty lady from the original post wants to be sold... what would you pay for a spotted 2015 kilo Kook?

    [​IMG]
     
  16. Aurora et luna

    Aurora et luna Well-Known Member Silver Stacker

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    Because I like you, I would offer you a space saver kilo bar in exchange. :p
     
  17. SpacePete

    SpacePete Well-Known Member Silver Stacker

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    You're a brave man. You haven't seen the state of the capsule!
     
  18. barsenault

    barsenault Well-Known Member

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    why don't you tell Ron and gang over at the mint to purchase it for spot plus what you paid over spot per ounce, afterall it's their fault. :) Plus, aren't they testing on why it is happening? I'm sure you can sell on eBay for spot plus what, .79? spot plus a buck per oz? You're definitely not getting full price for that, IF you highlight the spot, which you are doing. And I would do the same. :)
     
  19. dccpa

    dccpa Active Member

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    Feebay fees would be too high. A seller would be far better off to sell here near spot than go to ebay on a spotted coin.
     
  20. Gatito Bandito

    Gatito Bandito Active Member

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