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 Post subject: How to test for sterling
PostPosted: Sun Jun 02, 2013 9:37 pm 
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I purchased a lot of silver chains that were sold to me as sterling. They are indeed stamped 925. How can I go about verifying that they are silver and not plated brass or base metal? Is this something that can be done at a jeweler?

Jason

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 Post subject: Re: How to test for sterling
PostPosted: Sun Jun 02, 2013 9:55 pm 
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hi Jason

Simple way to test for sterling ... get out your specific gravity equipment and check the SG of you rchains .. if they are sterling the specific gravity will be 10.36

hope this helps

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 Post subject: Re: How to test for sterling
PostPosted: Sun Jun 02, 2013 10:44 pm 
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A jeweler who is familiar with acid testing will probably have both nitric acid and Schwerters solution, (nitric with some potassium dichromate). Nitric is easier when testing for plated stuff as a drop on the piece will tell you immediately if it's been plated since it will fizz vigorously and may turn green as well. A word of caution, if you're concerned about the look of the pieces, make sure to do the testing in an inconspicuous spot, since either solution will discolor the piece. Schwerters is kind of neat in that it can indicate the metal content of various metals in the piece by the color the solution turns.

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 Post subject: Re: How to test for sterling
PostPosted: Sun Jun 02, 2013 11:05 pm 
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George: Thanks for that idea. Unfortunately, I'm not set up at the moment for SG. LOL you should see my office.

Michael: Excellent. I'm not concerned at all about the appearance of the sacrificial piece. I have well over 100 pieces and non of them were pricy so i can give one to the acid gods to validate the rest.

J-

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 Post subject: Re: How to test for sterling
PostPosted: Mon Jun 03, 2013 5:52 am 
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While I do not advise cutting into a piece as it is normally unnecessary with normal plated gods In some cases it is advisable. Schwerters solution is available pre mixed from most of the vendors whom sell gold testing solutions, for the nitric acid I would suggest using a 14 K test solution although 10 will probably work as well. For a non destructive surface test X ray fluorescence is probably the most accurate, however you need to be doing a lot of this type of analysis to afford the high buy-in price ($20,000 or so).

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 Post subject: Re: How to test for sterling
PostPosted: Mon Jun 03, 2013 2:27 pm 
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I know, Jason, you're not set up for Specific Gravity, but I've used it somewhat frequently over the years to help with identifying metals.
Just in case, here is a good reference:
http://www.hauserandmiller.com/reference/melting.html


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 Post subject: Re: How to test for sterling
PostPosted: Mon Jun 03, 2013 4:05 pm 
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Wow Barbra, that's a GREAT chart! Thanks!

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 Post subject: Re: How to test for sterling
PostPosted: Tue Jun 04, 2013 3:33 pm 
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Jason wrote:
Wow Barbra, that's a GREAT chart! Thanks!


Indeedy. And if you copy & paste it into a spreadsheet, you can sort by specific gravity for ID purposes!

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 Post subject: Re: How to test for sterling
PostPosted: Sat Jun 08, 2013 7:31 am 
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Well, apparently no jewelers in my area are able to do the job for a fee that sounds reasonable. In fact, i only found one jeweler who could do an acid test and they wanted $25.00. Is that a reasonable price?

If anyone here is willing to do this for me I will pay you and you can keep the chain.

Jason

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 Post subject: Re: How to test for sterling
PostPosted: Sat Jun 08, 2013 8:58 am 
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Jason wrote:
Well, apparently no jewelers in my area are able to do the job for a fee that sounds reasonable. In fact, i only found one jeweler who could do an acid test and they wanted $25.00. Is that a reasonable price?

If anyone here is willing to do this for me I will pay you and you can keep the chain.

Jason

25$????!!! if i was in NYC i would do it for your for free,
buy Schwerters solution from amazon for 12$ and test it yourself,

http://www.amazon.com/Schwerters-Reagen ... B00C6PWH9Y

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 Post subject: Re: How to test for sterling
PostPosted: Sat Jun 08, 2013 10:54 am 
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Or, if it's something you plan on doing more than a few times, you can get a full test kit: http://www.ottofrei.com/Testing.html

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 Post subject: Re: How to test for sterling
PostPosted: Sat Jun 08, 2013 2:35 pm 
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I agree with these guy's Jason, do it yourself. It's very easy, takes seconds and gives excellent assurance that you either have silver or not. Make sure to wear safety glasses and rubber gloves. Those solutions can wreck your eyes and give you some long term staining on your fingers if you aren't careful.

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 Post subject: Re: How to test for sterling
PostPosted: Sun Jun 09, 2013 3:13 pm 
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Thanks for the advice guys. I'm going to purchase the complete kit. I don't need to test a ton of stuff, but I do need it on occasion.

I'll report back with my findings. :)

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 Post subject: Re: How to test for sterling
PostPosted: Sun Jun 09, 2013 7:01 pm 
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The acids really last a long time, so it's a good investment. 8)


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 Post subject: Re: How to test for sterling
PostPosted: Thu Jun 20, 2013 4:51 pm 
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Ok, I ordered the full kit. It will be here Monday.

I believe these chains have a light rhodium plate. Should I abrade one of them to expose the metal underneath to do the acid test?

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