# testing for silver



## whitesid (Jan 1, 2008)

is there any way that you can test for silver with out chemicals? a while ago i was metal detecting i found a melted blob of metal . it registered as silver on the metal detector and had a black tarnish on it. i know its not lead its to hard. so i was think it was really silver. but i don't have any chemicals right now. is there any other way to find out?


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## jimdoc (Jan 1, 2008)

If you found it on the beach it is probably aluminum
from people throwing their cans in the campfire.
Though aluminum should be a lot lighter than a
blob you would mistake for silver. Where did you find
it? If it was from a site that had a house burn down
maybe it could be silver. Jim


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## whitesid (Jan 1, 2008)

jimdoc said:


> If you found it on the beach it is probably aluminum
> from people throwing their cans in the campfire.
> Though aluminum should be a lot lighter than a
> blob you would mistake for silver. Where did you find
> ...


it was when they were digging up a park to make the road a little bigger. it was across the street from a old house from the 1700s. i know its not aluminum because it is not light like you said and because aluminum oxides white not black.


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## jimdoc (Jan 1, 2008)

Maybe it is pewter also.
Can you post a picture?


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## whitesid (Jan 1, 2008)

here it is. its next to a half dollar for size


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## jimdoc (Jan 1, 2008)

Maybe if you try to melt it with a propane torch?
If it is pewter it should melt much quicker than
if it is silver? I hit a ring that was marked P+
with a propane torch and it melted real quick,
my guess was that it must have been pewter.
You can see how hard it is to melt a junk silver
dime to compare any melting points.


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## whitesid (Jan 1, 2008)

ok
thanks


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## goldsilverpro (Jan 1, 2008)

If you can, determine the Specific Gravity. You'll need at least a .01 gram scale for accuracy. Just about any scale can be jury-rigged for SG measurements. Clean up the blob and weigh it normally. Then weigh it hanging in distilled water. Use a strong thread or a small string. The calculation is SG = Weight in Air/(Weight in air - Weight in Water). Then, look on a chart and find the possibilities.

http://www.sternleach.com/Images/Tech_Spec_various_material.pdf

Using a pocketknife, try to cut a sliver off the edge. Silver will cut cleanly, but not nearly as easily as lead or tin. Copper and most of it's alloys will cut with difficulty. They are, however, colored.

Examine the color of where you cut. Pure silver is the whitest metal on the planet. Even sterling is very white.


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## whitesid (Jan 1, 2008)

goldsilverpro said:


> If you can, determine the Specific Gravity. You'll need at least a .01 gram scale for accuracy. Just about any scale can be jury-rigged for SG measurements. Clean up the blob and weigh it normally. Then weigh it hanging in distilled water. Use a strong thread or a small string. The calculation is SG = Weight in Air/(Weight in air - Weight in Water). Then, look on a chart and find the possibilities.
> 
> http://www.sternleach.com/Images/Tech_Spec_various_material.pdf
> 
> ...


i have a .1 gram scale. when i did it had a mass of 24.7 grams in air and 4.0 i distilled water. so when i did the math it was a SG of 1.19 i had to do something wrong theres nothing with a sg close to that


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## goldsilverpro (Jan 1, 2008)

It can't only be 4.0 in water. It is probably around 22-23 grams in water. You may not have much luck with the .1 gram scale, although it can get within about .4 SG units, in accuracy, for your particular sample.

What happened with cutting slivers with the knife?


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## lazersteve (Jan 1, 2008)

You could use the density formula assuming there are no voids in the material.

Density = mass / volume.

Weigh the unknown in grams and divide by the amount of water it displaces in millliters.

For example if it weighs 24.7 grams and displaces between 2.1 mL and 2.47 mL of H20 it's density is 10-12 g/cc and it could be a silver alloy.

24.7 / 2.47 = 10
24.7 / 2.1 = 12
24.7 / 2.35 = 10.5 g/cc = pure silver

Pewter is mostly tin (90%+) and should have a density around 7.31 g/cc.

Specific gravity is just the density relative to the density of water.

Steve


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## goldsilverpro (Jan 2, 2008)

Steve,

The water displacement method is simple but often hard to utilize, accurately. The simplest way is to use a graduated cylinder - a graduate. However, this is best done on long, bulky, fairly narrow items. For small items, it's hard to read the marking differentials. When making measurements, the bottom of the meniscus is used, of course.

The best water displacement apparatus that I've seen consists of a tall narrow container with a down-sloping side-arm, with clear tubing running to a tared beaker. The container is first filled until it overflows and the overflow water is discarded - collect it a waste container and not the tared beaker. The object is then slowly placed in the container, without hardly disturbing the water and the overflow water is collected in the tared beaker (or, other vessel). The overflow water is weighed and the specific gravity is calculated quite accurately, assuming the water can be weighed to at least .01 grams. Use distilled water. At 39.2 deg F (4 deg C), I think, 1.000 mL of pure water weighs 1.000 grams and occupies 1.000 cc of space. If you want extreme accuracy, there are correction charts for other temperatures. 

One thing that would affect accuracy would be beads of water hanging up in the tubing or "steps" in the apparatus. However, the "water hang-up" may be fairly constant, after running the "zeroing water" through the apparatus. This tubing hang-up is due mainly to surface tension and can maybe be reduced by filling the tubing with a strong, maybe hot, soap solution and letting it set for awhile - rinse well. It's also best to, at least, soap clean the object to prevent air bubbles from forming on it. You can also stir a single drop of dishwasher soap into the water to help reduce clinging bubbles. Cavities also trap air and can give high results.

Sloshing the liquid around will create errors. Sometimes, when the object is in and everything settles down, the level is below the overflow. You might be able to correct this by adding water, from a tared container (squirt bottle, beaker, etc.) of water, until the water barely starts to overflow. The beaker or squirt bottle is then re-weighed. The "smoothness" of the overflow system could be important. 

Chris


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## Lino1406 (Jan 2, 2008)

Can you give an average thickness?
Silver is not attacked as badly as
that.


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## MarcoP (Jun 5, 2015)

Is it attracted by a magnet?


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