BEST WAY TO TEST PRECIOUS METALS (without a XRF Machine)

Discussion in 'General Precious Metals Discussion' started by Mint Silver Coins, Oct 19, 2019.

  1. Mint Silver Coins

    Mint Silver Coins Well-Known Member

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    Best way to Test Precious Metals ... in order of testing:

    1). Ping Test (for coins and small bars) suspend the coin on the tip of your left pointer finger (over your bed, to cushion the fall in-case it drops, until you are practiced in "pinging") and tap it gently on the edge (rim) with a known real coin ... it should have a long "sweet" high pitched ring ... it if is a "short" duller pitched ring, it is fake ...

    You can also get a free android app called "Bullion Test" on google play ... which will give you an accurate reading (it is worth the $5 upgrade though).

    2). 500g Digital Coin Scales are best ... and make sure to get the increments as 00.00g (and not 00.0g) ... as it will give you an exact reading ... the coin should never weigh more than 10% over weight (those that do are re-smelted) ... so an under weight coin is always fake ... and an overweight coin can not be more than 10% overweight otherwise it is fake.

    3). Digital Callipers ... coins and (non-freeform) bars have a set dimension and width, that you can check using Callipers ... (Scales and Callipers can be bought cheaply enough from Ebay) ... you can find (weight, dimension and width) coin specifications online ... if you can't find certain specifications, please feel free to message me :)

    4a). Specific Gravity Test ... eg: the Specific Gravity of 999 Silver is 10.46 ... how you calculate the S.G. of any metals ... of any size or shape under 500g is ...

    A.) calculate the dry weight eg. the coin weighs 31.27g dry
    B.) then calculate the wet weight (I use a water bottle with the top cut off and a bent coat hanger)
    C.) put the "cup" of water and the wire hanger suspended in it on the scales and tare it off (water must cover the coin holding section)
    D.) carefully place the coin on the stand (without disturbing the water level too much)
    E.) so let's say the wet weight was 2.99g
    F.) 999 Silver dry weight 31.27g / divided by wet weight 2.99g = 10.46g S.G. (confirmation that it is 100% beyond doubt genuine)
    -.) another example is ... 9999 Silver 10 oz. coin dry weight is 313.51g divided by 29.90g wet weight = 10.49 S.G. (also spot on)

    TIP: you can also just tie a cotton thread around the coin and dunk it under the water-line ... to calculate the wet weight (or you can make a suspension stand out of a coat hanger as per the attached photos)

    4b.) With the Specific Gravity Test make sure the S.G is very close to spot on ...
    as China can mimic the S.G. of 999/9999 Silver ... with fakes made from anti-friction alloys. (with a S.G. between 9.4 and 10.6)
    999 Silver has a S.G. of 10.46
    9999 Silver has a S.G. of 10.49

    and with Gold it can have a wafer or core of Tungsten
    (Tungsten 19.60 S.G. is close to the 19.32 S.G of 9999 Gold)
    so you must also confirm, weight, dimension and width to be 100% sure.

    -.) I do not find the Neodymium Magnets to be of any use anymore, as the new anti-friction metals, that China makes the Silver fakes from, re-act like Silver.

    PM Testing 1.jpg PM Testing 2.jpg PM Testing 3.jpg PM Testing 4.jpg

    I've created an easy to use, excel workbook file with a complete S.G. list ... for all metals and variations eg. 14k Gold or 15% iridium platinum ... you just simply need to enter the dry and wet weight data ... and it will auto-calculate the S.G.

    If any SS members would like a copy, just message me with your email address ... with the conversation titled as "Specific Gravity Test"

    I am also happy to answer any random questions, that anyone may have re: Precious Metals
    Cheers ... Toni (Mint Silver Coins) :)
     
    silverhair, Skyrocket and 66rounds like this.
  2. Skyrocket

    Skyrocket Well-Known Member Silver Stacker

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    Thanks but are you sure the magnet test is no good now because of new Chinese anti-friction metals? Does it slide down the same distinct way?
     
  3. Mint Silver Coins

    Mint Silver Coins Well-Known Member

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    One is a "nano" second faster, than the other (I forget which, is which atm :confused:)
    but you would need a double lane coin slide ... and an identical "known genuine" coin
    to run down the slide, and let go, at the exact same second, as the one you are testing,
    and you would have to repeat the test a few times, for any kind of certainty.

    If you use just a small Neodymium Magnet on its own and slide it directly down the coin,
    the similarity is so close (between anti-friction alloys & Silver) that you won't be able to tell,
    with any real certainty. :oops:

    Having said that, a lot of the older fakes were silver plate over a variety of magnetic metals,
    so it was much easier to tell ... as the magnet would stick to the coin or slide off really slowly.

    I learnt my lessons well, after buying 5 fakes off Ebay, when I first started buying years ago,
    I still keep them as a reminder (plus also because it was way past the 30 day Guarantee limit)
    so I just wore the cost of my newbie mistakes :eek: ... and researched all I could about fakes. :cool:

    Now I know better :rolleyes: ... and I eventually learnt that Paypal has a Guarantee for upto 180 days ;)

    Cheers :)

    PS ... 2 of my early buying blunders ... is the infamous 2015 Proof Salt Water Crocodile (in capsule only)
    and the seller on Ebay called Horomatics ... who I later came to realize, sells/auctions off at least one
    2013 Opal Kangaroo Proof Coin (in capsule only) per week ... so by my accounts that's at least
    200 x Opal Kangaroo Proof Coin's (in capsule only) so far ... oh, well you live and learn :p
     
    Last edited: Oct 20, 2019
  4. Mint Silver Coins

    Mint Silver Coins Well-Known Member

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    All members are more than welcome to share their tales of woe :eek:
    about "fakes" they have bought (or know of) :mad: ... on this thread
    that way a newbie might read the posts, and know to steer clear :cool:
     
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