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 Replies: 13 / Views: 1,866 |
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Valued Member
United States
247 Posts |
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Valued Member
 United States
247 Posts |
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Bedrock of the Community
United States
62064 Posts |
It could be a rolling of the stock material issue or a poor mix on the outer clad layers. Either way it is nothing with a premium. Sorry.
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Valued Member
United States
247 Posts |
Thats cool, I wasn't expecting anything. I just wanted to hear some ideas as to what could have caused it. Thanks for replying!
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Pillar of the Community
United States
3592 Posts |
Bluntedbobylon...just remember most people are at work so sometimes it takes till the evening to get answers  |
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Pillar of the Community
United States
601 Posts |
I agree with coop- I've seen similar coins and I think that environmental conditions can bring out the contrast of impurities in the alloy. It's is fun looking if not collectible and a worthwhile coin to question!
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Valued Member
United States
247 Posts |
"Bluntedbobylon...just remember most people are at work so sometimes it takes till the evening to get answers" Doh!  Sorry, it's my day off so I didn't even think of people being at work. |
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Bedrock of the Community
United States
12437 Posts |
I attribute this appearance to the set up of the metal stock. The clad sheets of metal are rolled between two heavy metal drums to obtain the proper thickness before the blanks are punched. The rollers can have a rough surface and also be contaminated with grease/oil which then transfers to the blanks. When you see these thin parallel dark lines that match up on both sides of the coin, it can almost always be attributed to a rolling issue. This phenomenon is also frequently seen on pre-1982 Lincolns.
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Pillar of the Community
United States
601 Posts |
Wow, that's interesting. I think it's going to make me rethink how I look at those type of planchets. Can this appearance manifest on a single side of the coin biokemist?
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Valued Member
United States
247 Posts |
Thanks biokemist6! It's a keeper.
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Pillar of the Community
United States
4000 Posts |
So, basically this is a quarter "woody"?
Would that fall under some kind of alloy mix or planchet error?
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Bedrock of the Community
United States
12437 Posts |
I do not recall ever seeing a one-sided example. I think it would be possible but more likely that both rollers would be dirty and abraded. I cannot see how one of these clad planchets could be considered an alloy error if the lines are parallel to each other on both sides. An alloy error would affect the outer clad layers independently because an alloy error would occur before the clad layers were bonded, the odds of alloy graining matching perfectly on two independent sheets of metal would be very small indeed.
The Lincoln cents are commonly considered to be "woodies" in the classic sense of a poor alloy mix but the Memorials affected have a much different appearance from the alloy streaks of the early wheaties. Their perfectly thin parallel nature made me reconsider the alloy issue and the only explanation that fits is a roller issue. There should also be oxidation at work to create the contrast, more than likely increased by the residue left from the rollers.
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Pillar of the Community
United States
2736 Posts |
The source of these streaks is not really understood. Some say they're roller marks, others say they're marks from a rotating descaling brush. But this is all speculation.
Error coin writer and researcher.
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Pillar of the Community
United States
3174 Posts |
Why are there so many unknown facts? Doesn't anybody know an employee from one of the mints?Are mint employees not allowed to speak to the public?Just curious!  |
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Replies: 13 / Views: 1,866 |
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Posted 03/24/2011 3:53 pm
