Testing silver coins with an ultrasonic thickness gauge

Discussion in 'Silver' started by mdbruhn, Sep 26, 2013.

  1. mdbruhn

    mdbruhn New Member

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    Hello all,

    here is a question for anyone with coins AND an ultrasonic thickness gauge.

    Can you get any kind of meaningful reading off your coins with all the uneven surfaces?

    I know it works on a bar, I've tried it. I don't have any coins (yet) I'm favouring bars because it is so easy to test S.G. and speed of sound on any bar with a lot of flat surfaces.

    Anyone tried this? any opinions? any thought/comments?
     
  2. Captain Kookaburra

    Captain Kookaburra Well-Known Member Silver Stacker

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    Nope.... Need an XRF for coins.
     
  3. mdbruhn

    mdbruhn New Member

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    thanks for that info Captain Kookaburra.

    Yeah that makes sense, wishful thinking on my part :)

    One other question for you: Will an XRF detect a silver plated lead alloy? :/
     
  4. Captain Kookaburra

    Captain Kookaburra Well-Known Member Silver Stacker

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    It will as long as the the plating is thinner than 30-50 microns.

    Coins - No Problems.

    Thickly plated Silver over Lead ... Tricky. But that's when you would use your ultrasonic tester.
     
  5. mdbruhn

    mdbruhn New Member

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    OK, so all I need to do is convince my boss that we really need that XRF machine for testing the secondhand steel we buy ;)
     
  6. Midnight Man

    Midnight Man Member Silver Stacker

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    I won't just "say thanks" for brevity here, because that doesn't tell you that I have found exactly as Cap'n Kook has reported - for the thickness guage to work, you must have good, even contact for the sensor - impossible on a coin, and sometimes even challenging on a Perth Mint blob (poured bar), casts work incredibly well, as you've probably found out yourself :)
     
  7. goanna

    goanna Member Silver Stacker

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    How about if you did the coin across the diameter, ie edge to edge?
     
  8. Midnight Man

    Midnight Man Member Silver Stacker

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    Have tried it (on 1oz coin), no luck for me, and if the coin has a milled edge, you can most certainly forget it. The problem is that there just isn't enough "meat" on a 1oz coin to measure.

    I don't have bigger than 1oz coin to try, so - maybe on bigger coins? Unsure.
     

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