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JerrySpringer
Penny Hoarding Member
669 Posts |
 Posted - 11/08/2009 : 19:50:24
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I have noticed that from silver dollars to dimes, a nice ringing sound is made by them if you balance the coin on your fingertip and tap it with another coin. I have some unidentified Asian coins from roll searches that pass the ring test. Possibly silver? No dates on them in numerical characters. I'll see if I can dig up a world coin book to compare them to.
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Country
1000+ Penny Miser Member
USA
3121 Posts |
Posted - 11/08/2009 : 20:00:51
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Post some photos. I'm sure some Realcenter, maybe myself, will tell you what you've got. 
Magnet test works too. |
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– Theodore Roosevelt
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JerrySpringer
Penny Hoarding Member
669 Posts |
Posted - 11/08/2009 : 20:53:53
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quote:
Magnet test works too.
The one coin I found in a nickel roll the other day does not stick to a magnet. It passes the ring test. My imaging tools right now are not great. Digital camera and cell phone camera do not have good resolution and/or close-up focus ability. I will probably need to drag out my scanner to get a best resolution photo of the coins. I'll describe the coin I found the other day. It has a lion-head,with a flowing mane, on the obverse with a growling, tooth-exposed open mouth. The reverse has a man and woman in a long dress holding a hammer and wrench, respectively, in his right, and her left hand, with their arms held up in a Y-shape. The numbers 2 and 5 are on the coin, flanking the left side and right side, with the two people sandwiched between. I'll see if I can find a picture online somewhere meanwhile. |
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tmaring
Penny Collector Member
USA
302 Posts |
Posted - 11/08/2009 : 21:19:22
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For identifying foreign coins you should have copies of Krause Pubs World Coins catalogue, and I'd recommend also having UNUSUAL WORLD COINS for those many not-quite-coin items.
The ring test for silver is primarily a counterfeiting test, NOT a test for silver per se. Counterfeiting of US silver coins using zinc was rampant in the middle 1800s... zinc does not ring. So flipping a half or dollar to see if it "rings true" (this is the origin of that phrase) makes sense. On the other hand, other metals like copper and brass will ring also if the thickness and diameter of the coin are proportioned right. So just because it rings does NOT mean it's silver... just means it's not zinc or lead.
The magnet test ONLY works for iron based alloys or rather pure nickel... white bronzes will NOT stick to magnets.
Foreign coins that are actually silver may be rather low grade. Silver/Copper is a eutectic alloy system, which means that as you mix the metals the melting point of the alloy is lowered until it reaches its minimum of about 1450 degrees F at 72% silver 28% copper. You might recognize that a lot of Mexican and other foreign silver coins utilize this eutectic alloy in order to minimize smelting costs and stretch out their silver supply. So that's why the coin catalog is necesary, to identify the alloys. |
Tom Maringer
Shire Post Mint
Springdale, Arkansas |
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Bluegill
1000+ Penny Miser Member
USA
1964 Posts |
Posted - 11/08/2009 : 21:22:36
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It sounds like an Ethiopian 25 cent.
If it is, it is 3.7 grams of CuNi.
World Coin Gallery is a good website for identifying foreign coins.
You must be logged in to see this link.
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JerrySpringer
Penny Hoarding Member
669 Posts |
Posted - 11/08/2009 : 21:29:06
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| Bingo. A google check on lion+head+coin showed an Ebay item of earrings with exact same lion. Oh well, I thought I had me a silver one. Ring test is not sufficient test. Bet a 1982 Roosevelt dime makes the ringing sound too, uggh. |
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JerrySpringer
Penny Hoarding Member
669 Posts |
Posted - 11/08/2009 : 21:31:31
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| Thanks folks. I'll bookmark the world coin gallery site for the other unidentified coin I have. |
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Ring test for silver a pretty good method?
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