# How can I prove silver without a hallmark is pure silver? **URL:** \ **Category:** Factual Questions\ **Created:** [October 20, 2013, 3:47am UTC](https://boards.straightdope.com/t/how-can-i-prove-silver-without-a-hallmark-is-pure-silver/671706 "2013-10-20T03:47:14Z")\ **Posts on this page:** 17\ **Page:** 1
**Author:** ![Superhal](https://avatars.discourse-cdn.com/v4/letter/s/b4bc9f/32.png) [@Superhal](https://boards.straightdope.com/u/Superhal)\ **Post date:** [October 20, 2013, 3:47am UTC](https://boards.straightdope.com/t/how-can-i-prove-silver-without-a-hallmark-is-pure-silver/671706/1 "2013-10-20T03:47:14Z")
This is probably the best deal on silver anywhere: [http://www.providentmetals.com/500-troy-ounces-999-fine-silver-shot.html](http://www.providentmetals.com/500-troy-ounces-999-fine-silver-shot.html) However, they don’t recommend it as an investment because it isn’t hallmarked. But, i think it would be fairly easy to prove that it is pure silver without a destructive test or expensive testing equipment. My idea is a water displacement test. Take equal weights of shot with a known amount of silver, say a 31.1 gram .999 round. Then, the water displacement of both should be exactly equal. Is there a better way? ---
**Author:** ![MikeS](https://avatars.discourse-cdn.com/v4/letter/m/919ad9/32.png) [@MikeS](https://boards.straightdope.com/u/MikeS)\ **Post date:** [October 20, 2013, 3:50am UTC](https://boards.straightdope.com/t/how-can-i-prove-silver-without-a-hallmark-is-pure-silver/671706/2 "2013-10-20T03:50:04Z")
Your test doesn’t prove that it’s silver; it proves that it has the same density as silver. It could well be some base metal alloy that has the same density as silver and appears superficially the same. ---
**Author:** ![njtt](https://avatars.discourse-cdn.com/v4/letter/n/ecd19e/32.png) [@njtt](https://boards.straightdope.com/u/njtt)\ **Post date:** [October 20, 2013, 7:58am UTC](https://boards.straightdope.com/t/how-can-i-prove-silver-without-a-hallmark-is-pure-silver/671706/3 "2013-10-20T07:58:28Z")
Did this idea come to you in your bath? ---
**Author:** ![samclem](https://avatars.discourse-cdn.com/v4/letter/s/a9a28c/32.png) [@samclem](https://boards.straightdope.com/u/samclem)\ **Post date:** [October 20, 2013, 12:02pm UTC](https://boards.straightdope.com/t/how-can-i-prove-silver-without-a-hallmark-is-pure-silver/671706/4 "2013-10-20T12:02:22Z")
> [@Superhal](#): > > This is probably the best deal on silver anywhere: Except you’re gonna get killed when you go to sell it. Our normal buy/sell spread on marked 100 ounce .999 fine bars is-- we purchase at spot and sell at $1.75 over spot. No assay required. With the unmarked shot you’re paying a 50 cent premium over spot to start with but there’s little likelyhood you can get spot - $1.25 on the sell end. ---
**Author:** ![Malacandra](https://avatars.discourse-cdn.com/v4/letter/m/45deac/32.png) [@Malacandra](https://boards.straightdope.com/u/Malacandra)\ **Post date:** [October 20, 2013, 1:18pm UTC](https://boards.straightdope.com/t/how-can-i-prove-silver-without-a-hallmark-is-pure-silver/671706/5 "2013-10-20T13:18:06Z")
> [@MikeS](#): > > Your test doesn’t prove that it’s silver; it proves that it has the same density as silver. It could well be some base metal alloy that has the same density as silver and appears superficially the same. Copper and nickel are both close to silver; wrap a cupro-nickel alloy sheath around a lead core, and getting a perfect match is left as an exercise for the student. For added verisimilitude, electroplate with actual silver. The reason why the eureka test is such a good one for gold is because it’s really hard to substitute something of similar density (tungsten’s not a bad fit, but substituting tungsten for gold comes with problems of its own). ---
**Author:** ![aNewLeaf](https://avatars.discourse-cdn.com/v4/letter/a/ac91a4/32.png) [@aNewLeaf](https://boards.straightdope.com/u/aNewLeaf)\ **Post date:** [October 20, 2013, 1:19pm UTC](https://boards.straightdope.com/t/how-can-i-prove-silver-without-a-hallmark-is-pure-silver/671706/6 "2013-10-20T13:19:09Z")
Some metal recycling places have a little laser gun that can take a spectrometer reading. Call around, see if there’s one in your area. ---
**Author:** ![Isilder](https://avatars.discourse-cdn.com/v4/letter/i/cc9497/32.png) [@Isilder](https://boards.straightdope.com/u/Isilder)\ **Post date:** [October 21, 2013, 11:07am UTC](https://boards.straightdope.com/t/how-can-i-prove-silver-without-a-hallmark-is-pure-silver/671706/7 "2013-10-21T11:07:37Z")
> [@MikeS](#): > > Your test doesn’t prove that it’s silver; it proves that it has the same density as silver. It could well be some base metal alloy that has the same density as silver and appears superficially the same. As the weight/volume calculation shows AVERAGE density, it doesn’t even show that the item is homogenise, it could be some lead, some brass (or other filler), and silver over the top. The silver bought off ebay is often a silver dipped billet of junk. Oh its not even bullion, its ‘shot’ like its just reclaimed from jewellry… said to be 0.999 but what is it really ? and why is it SPOT price if its not bullion ? It could be a little above the price you’d pay someone for beat up silverware. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [October 21, 2013, 1:53pm UTC](https://boards.straightdope.com/t/how-can-i-prove-silver-without-a-hallmark-is-pure-silver/671706/8 "2013-10-21T13:53:09Z")
It will only cost you 11 grand plus change to find out. How you go wrong with a deal like that? ---
**Author:** ![Dewey\_Finn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dewey_finn/32/4222_2.png) [@Dewey\_Finn](https://boards.straightdope.com/u/Dewey_Finn)\ **Post date:** [October 21, 2013, 2:08pm UTC](https://boards.straightdope.com/t/how-can-i-prove-silver-without-a-hallmark-is-pure-silver/671706/9 "2013-10-21T14:08:52Z")
> [@samclem](#): > > Except you’re gonna get killed when you go to sell it. It _might_ just be pure silver. Perhaps it’s the leftover silver from some factory process; they could have sold it to a metal refinery but they would have gotten something less than spot. So on the greater fool theory, they offer it for sale at slightly _above_ spot. Clever on their part. ---
**Author:** ![samclem](https://avatars.discourse-cdn.com/v4/letter/s/a9a28c/32.png) [@samclem](https://boards.straightdope.com/u/samclem)\ **Post date:** [October 21, 2013, 11:05pm UTC](https://boards.straightdope.com/t/how-can-i-prove-silver-without-a-hallmark-is-pure-silver/671706/10 "2013-10-21T23:05:21Z")
The seller is reliable and indeed selling .999 fine silver. That’s not the problem. ---
**Author:** ![eltro102](https://avatars.discourse-cdn.com/v4/letter/e/7cd45c/32.png) [@eltro102](https://boards.straightdope.com/u/eltro102)\ **Post date:** [October 23, 2013, 10:05pm UTC](https://boards.straightdope.com/t/how-can-i-prove-silver-without-a-hallmark-is-pure-silver/671706/11 "2013-10-23T22:05:20Z")
find a werewolf ---
**Author:** ![Duckster](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/duckster/32/1244_2.png) [@Duckster](https://boards.straightdope.com/u/Duckster)\ **Post date:** [October 23, 2013, 10:31pm UTC](https://boards.straightdope.com/t/how-can-i-prove-silver-without-a-hallmark-is-pure-silver/671706/12 "2013-10-23T22:31:07Z")
> [@Superhal](#): > > However, they don’t recommend it as an investment because it isn’t hallmarked. There’s your answer. If you want to go to all of that trouble to prove it has real value, there’s a bridge I can sell you. I only take 1964 Kennedy half dollars at face value, though. 🙂 ---
**Author:** ![dstarfire](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dstarfire/32/5762_2.png) [@dstarfire](https://boards.straightdope.com/u/dstarfire)\ **Post date:** [October 24, 2013, 9:44pm UTC](https://boards.straightdope.com/t/how-can-i-prove-silver-without-a-hallmark-is-pure-silver/671706/13 "2013-10-24T21:44:20Z")
The folks on “Pawn Stars” use nitric acid to confirm it’s silver or not. They also take core samples or cut a small notch to get at the deeper material and check that, too. ---
**Author:** ![Superhal](https://avatars.discourse-cdn.com/v4/letter/s/b4bc9f/32.png) [@Superhal](https://boards.straightdope.com/u/Superhal)\ **Post date:** [October 24, 2013, 11:15pm UTC](https://boards.straightdope.com/t/how-can-i-prove-silver-without-a-hallmark-is-pure-silver/671706/14 "2013-10-24T23:15:22Z")
> [@dstarfire](#): > > The folks on “Pawn Stars” use nitric acid to confirm it’s silver or not. They also take core samples or cut a small notch to get at the deeper material and check that, too. Acid tests are usually destructive. The electronic device mentioned above is too expensive, about $20k. ---
**Author:** ![Dewey\_Finn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dewey_finn/32/4222_2.png) [@Dewey\_Finn](https://boards.straightdope.com/u/Dewey_Finn)\ **Post date:** [October 24, 2013, 11:17pm UTC](https://boards.straightdope.com/t/how-can-i-prove-silver-without-a-hallmark-is-pure-silver/671706/15 "2013-10-24T23:17:33Z")
What is your goal with regarding to possibly purchasing this silver? Do you want to use it in some industrial process? Do you want to make jewelry? Or do you view this as a cheap way to buy silver as an investment? ---
**Author:** ![Yllaria](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/yllaria/32/3452_2.png) [@Yllaria](https://boards.straightdope.com/u/Yllaria)\ **Post date:** [October 25, 2013, 12:00am UTC](https://boards.straightdope.com/t/how-can-i-prove-silver-without-a-hallmark-is-pure-silver/671706/16 "2013-10-25T00:00:48Z")
> [@Superhal](#): > > Acid tests are usually destructive. The electronic device mentioned above is too expensive, about $20k. Our local coin shop has one. If I had silver to sell, that’s where I’d be taking it. We’ve checked around and they buy for the highest prices in town. ---
**Author:** ![asterion](https://avatars.discourse-cdn.com/v4/letter/a/4da419/32.png) [@asterion](https://boards.straightdope.com/u/asterion)\ **Post date:** [October 25, 2013, 12:49am UTC](https://boards.straightdope.com/t/how-can-i-prove-silver-without-a-hallmark-is-pure-silver/671706/17 "2013-10-25T00:49:00Z")
> [@aNewLeaf](#): > > Some metal recycling places have a little laser gun that can take a spectrometer reading. Call around, see if there’s one in your area. Are they using a [LIBS](http://en.wikipedia.org/wiki/Laser-induced_breakdown_spectroscopy)? Sure, the plasma generated doesn’t make much of a mark, but I wouldn’t consider that a non-destructive test, even if others do.