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Kali Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 06:25 PM
Original message
Not sure which forum to post - testing silver
Any easy tests for silver using common household chemicals? Found a chunk of soft, heavy (silver - duh) metal that looks like it might be an industrial/electrical part - could it be silver? - Perhaps I will take a photo and cross post in Science as well but for now this in GD.
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Ediacara Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 06:36 PM
Response to Original message
1. Can you calculate its density?
Silver's should be 10.5 g/ml
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Kali Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 06:48 PM
Response to Reply #1
3. actually I can probably do this, I have a scale
weigh it then see how much water it displaces? right? hmm do I have any acurate volume measuring cups that it will fit in? hmmm oh does altitude matter? probably not (4500 feet)
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Ediacara Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 06:53 PM
Response to Reply #3
4. I don't think it'll matter that much
make sure your measurements are metric and are in grams and mililitres (or cubic centemeters, which is a different name for the same thing).

Does the metal have any subtle color to it? Is it slightly yellow? Gray? Blue? Can you test its hardness and compare it to the Moh's Scale? It should be about 2.5.
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Kali Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 07:31 PM
Response to Reply #4
5. sorry to be so slow

ack! I lost my reply when forum got switched, also on really slow dial up - photos taking forever

OK soft - scratches easily with cheap pocket knife, silver colored (I like silver jewelry - its warm, if I can use that term - and so is this object

Weighs 80 grams, displaced about 1/4 teaspoon of water (I THINK one teaspoon = 5 cc'c but can't remember) but not sure my tecnique was very good - I filled a small bowl to just above rim, with surface tension, then caught the overflow from dropping object in a second container and measued that.

here are a couple pix:




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eppur_se_muova Donating Member (1000+ posts) Send PM | Profile | Ignore Wed Jan-18-06 05:20 PM
Response to Reply #3
38. Do it the way Archimedes did!
Edited on Wed Jan-18-06 05:23 PM by eppur_se_muova
Tie a small thread to the object and suspend it from the weighing pan of a balance. Now, place a large bowl of water under the object and raise it until the object is completely submerged, but not touching the bowl. The object will be slightly lighter in weight because of the buoyancy of water. The difference in these two weights is just the weight of an equal volume of water! (Optionally, at this point, run naked through the streets shouting "eureka!". It's traditional.) So now you divide the mass of the object by the mass of the water. The results is the specific gravity, which is the same as the density if you use the metric units of density, g/ml.

Lead: 11.34
Silver: 10.5
Copper: 8.92
Nickel: 8.90
Iron: 7.86
Tin: 7.28
Zinc: 7.14

Alloys tend to have densities between those of their constituents, but can actually be higher or lower in some cases. My bet is "nickel silver" or "German silver" as someone else posted already.
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Canuckistanian Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 06:37 PM
Response to Original message
2. Here are some ideas...
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Kali Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 07:42 PM
Response to Reply #2
6. dang - fresh out of iron sulfide and powdered sulfer
tried the onion, no change - inconclusive IMO.

(also double checked for magnatism - none)
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Redstone Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 07:57 PM
Response to Reply #6
7. That there is what's called a spade lug.
It plugs into a spade terminal.

I'm suprised it's not made of copper. But I guarantee you it's not made of silver. If it's white, it may be a zinc diecasting, though it looks to be machined rather than cast.

Could be white bronze.

If it were silver, it would feel unnaturally heavy.

Redstone
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Kali Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 08:07 PM
Response to Reply #7
10. It does feel unnaturally heavy!
I think it has been altered a little AFTER being cast...is zinc heavy?

(I've done some jewelry in the past - casting bronze and silver...)

what is white bronze?
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Redstone Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 08:16 PM
Response to Reply #10
13. Diecast zinc isn't real heavy.
White bronze is an alloy of copper, tin, and zinc. it's mostly used for electroplating, because it is nice and white like silver plating, and is solderable, but doesn't tarnish like silver plating over brass does. It's also known (in plating formulations) as Alballoy or IP-23.

What would weigh a lot would be a nickel-heavy copper alloy of brass or bronze (bronze is copper and tin; brass is copper and zinc, but many of these have some quantity of nickel as well).

Because it's obviously a spade lug of some kind (the bulge at the end of the "tongue" would be where the mating terminal would have a spring member for "snap" mating), it's highly unlikely that it would be any kind of silver alloy, because tarnish would be a problem (the oxides in tarnish increase electrical resistance by orders of magnitude).

And unless it's 99.9 (fine) silver, it would be tarnished as hell after sitting for years.

Redstone
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applegrove Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 08:17 PM
Response to Reply #13
14. If it makes you itchy - it could be zinc. Like I said - keep it away from
you till you know what it is.
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Kali Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 08:31 PM
Response to Reply #14
24. I'm always itchy - never heard of zinc-itchy connection...
more info, please?
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applegrove Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 08:40 PM
Response to Reply #24
28. Shot in the dark.
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Scout1071 Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 09:03 PM
Response to Reply #13
36. Redstone......I'm so impressed with you right now.
I don't understand half (or more) of what you said, but I'm impressed nonetheless.

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Richard Steele Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 08:21 PM
Response to Reply #7
18. "Spade lug", thank you! I couldn't remember that term!
See my post below; I have occasionally come across
items like this that were this same alloy.
(spent 7 years doing power line construction)
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applegrove Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 07:58 PM
Response to Original message
8. Silver is not strong enough for industrial use like this. Did you clean
it? I once picked up a couple of very pretty blue glass things - turned out they likely were from a telephone poll and may have been covered in PCBs.

Don't touch it!
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Kali Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 08:11 PM
Response to Reply #8
11. Silver is not strong enough for industrial use - yeah that is what
I think - but the feel! It was found a long time ago and has been washed, not really much else - but handled and stuck in a drawer for like a year or more...
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Redstone Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 08:19 PM
Response to Reply #8
15. Don't be afraid of old glass insulators.
Only a small percentage of them would have been anywhere near the transformers that contained PCBs. And if they were, well...glass is not porous, so they wouldn't have absorbed any PCB-containing oil.

Redstone
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applegrove Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 08:21 PM
Response to Reply #15
19. Well I learnt my lesson.
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qnr Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 07:59 PM
Response to Original message
9. This is way too serious a subject. My brain hurts.
Good luck though :)
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Richard Steele Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 08:12 PM
Response to Original message
12. I hate to be a wet blanket, but that's probably not silver.
You are dead-on when you guess it is an electrical part.
That looks like a piece of a large, heavy-duty electrical "switch"
of some sort. A switch designed to carry current for a large factory,
or a small town.

I have found a few such parts which were made from the same type of alloy;
it's actually a copper compound with small amounts of Nickel and Zinc.

It is commonly referred to as 'German silver' or 'nickel silver';
and it was originally used as a cheap silver substitute for jewellery and etc.
I think it gets used for high-capacity electrical parts like this
because it has better resistance to oxidation than pure copper.

It's still cool though.
I would frame it, and enjoy it just as ART.
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Kali Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 08:21 PM
Response to Reply #12
17. Or jewelry?
Edited on Tue Jan-17-06 08:22 PM by Kali
edit to add ;-) so you know I am kidding
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Richard Steele Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 08:24 PM
Response to Reply #17
21. Totally! GOOD jewellery is ART that you carry around with you.
My best(imnsho) jewellery incorporates 'found objects';
the only ring I ever made and decided to keep for myself
features a rusty nail I found on the sidewalk.
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Kali Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 08:41 PM
Response to Reply #21
29. I'm telling you it IS heavy - maybe some rap star would
want to wear it, but belt buckle is about the only place I think it would be comfortable! 80 grams!

but yeah I could see some velvet or leather going throught the holes, a wrap or two and a decorative knot, maybe some other beads (lapiz) as well...hmmmmm
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Rabrrrrrr Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 08:19 PM
Response to Original message
16. Here's the easiest, though slightly tricky, way to do it -
Place your lump on a thermonuclear device, with a temperature sensor. Set of the device, and - this is the tricky part, because the temperature will go up VERY fast - see what the temperature was when the lump boiled away. If it was 2435K, then it was silver.
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Kali Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 08:43 PM
Response to Reply #16
30. ...
:rofl: :toast:
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HysteryDiagnosis Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 08:22 PM
Response to Original message
20. Silver contact for a magnetic relay. Photos....






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Kali Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 08:26 PM
Response to Reply #20
22. oooooo just when I had about given up!....
seriously, the lack of tarnish after sitting around combined with the other experts above is pretty much saying NOT silver. :(
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HysteryDiagnosis Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 08:28 PM
Response to Reply #22
23. Another photo... small but perhaps closer to what you have....
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Kali Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 08:37 PM
Response to Reply #23
26. So these are photos of silver parts?
hard to tell scale, but wonder what Redstone and others have to say?
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HysteryDiagnosis Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 08:44 PM
Response to Reply #26
31. Could be simply silver anodized or coated.... on a cheaper base
metal to keep costs down.
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Redstone Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 08:38 PM
Response to Reply #23
27. That's the receptacle half of a knife switch, isn't it?
His part could be the blade for a knife switch, rather than a spade lug as I initially thought.

Redstone
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HysteryDiagnosis Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 08:45 PM
Response to Reply #27
32. As big as it looks... considering the amperage it should carry....
I was thinking the rapid contact and release of a mag switch was where it might live.... not really sure, just trying to help a little...
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Redstone Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 08:50 PM
Response to Reply #32
34. Given your other post, I think you may be on to something.
And the bulb at the end of the "tongue" would help the other part of the switch retain it mechanically to prevent an unwanted disconnection...you may very well have the answer.

Redstone
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Redstone Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 08:36 PM
Response to Reply #20
25. But silver isn't magnetic.
You must be thinking of silver PLATED parts.

Redstone
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HysteryDiagnosis Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 08:47 PM
Response to Reply #25
33. Right.... contacts such as these are sometimes bolted inside a
switch housing that has coils to provide the magnetic thrust to snap these contacts together and apart rapidly to minimize arcing, silver being such a great conductor is often applied to contact faces for this reason.....
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NNadir Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 09:00 PM
Response to Original message
35. A slightly troublesome test.
If one can obtain nitric acid from a photography shop, one could dip a portion of the object in the acid (careful, nitric acid is corrosive). The silver, if it is silver, should react generating a brown gas. The resulting solution should be colorless. Mixing the nitric acid solution, after sufficient silver has dissolved (a small amount) with a solution of table salt will produce a white precipitate. Once the precipitate is collected (free of the nitric acid solution), it should be possible to redissolve it with ammonia solution.

These tests are generally unambiguous. The first two reactions (dissolution and precipitation) can indicate lead under certain conditions, but usually this is not the case since only one oxidation state (II) exhibits an insoluble chloride.

Also the solubility of any black tarnish on the metal in ammonia is another indicator.
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Kali Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Jan-17-06 11:28 PM
Response to Reply #35
37. Yeah, that's the classic test, but again I don't have any of those
chemicals, not even ammonia! - I looked to see if I could clean it a bit - there isn't much in the way of tarnish, but sometimes it takes a while - I have some nice jewelry that I hardly wear, that doesn't tarnish that much and yet others that turn black pretty fast...


I just want to thank everybody - you've been great with the info. When I remember to take this with me I will stop at a coin exchange place in Tucson that I am pretty sure can test it. I will be sure to post the results.

Kali


PS
Redstone, I'm a her. :yoiks:
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