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Moderator
 United States
97925 Posts |
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Valued Member
 United States
82 Posts |
Edited by Adam C Vance
02/14/2021 12:30 pm
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Bedrock of the Community
United States
19230 Posts |
Given the photos provided, I see a range of common, circulated '70 D memorial cents. Copper cents take on a variety of coloration over years of circulation--some coins gather crud, some are exposed to different 'corrosive' environments (which can result in environmental toning), some coins are cleaned by well-meaning people, some coins are colored-in by kids (and the coloring partially wears off), etc.
The more Lincoln cents one comes across, the more variety in appearance one will see. I've been searching Lincoln cents for decades and have seen quite a variety when it comes to coloration/appearance.
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Bedrock of the Community
United States
62064 Posts |
Check to see if the coin is normal weight? That can affect the sound. The color can be altered with using the wrong solutions on it. (Also can thin a coin and weaken the devices if an acid is used)
Copper cents and zinc cents do sound different on a table.
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Pillar of the Community
United States
7516 Posts |
Looks like it was a buried coin at one time and the chemical reaction due to the soil and moisture have done their number on this coin before it was cleaned.
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Valued Member
United States
82 Posts |
Thank you now I know I did not know about ccorrosive where on a coine thats pretty neat
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Pillar of the Community
2145 Posts |
Quote:
Light dont do the coine justis and I shall deffiantly Wahigh the coine I'm quite interested in If you are running a voice recognition program you might want to see if it's operating properly also. |
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Valued Member
United States
82 Posts |
No I'm sorry I'm just not good at English even tho it's my primary language I was just pushed ahead every year with Ds and Fs on my report card because I was older than the other students I'm sorry for my bad grammar I'll try to find a voice to text soft where......and I'm still working on getting the scail its hard when my friend works and wrecked his car this winter and my room mate works and granny can't walk or get out any more and we only have one car I'm sorry I'll do my best to get it tonight if not tomorrow if there booth off work
Edited by Adam C Vance
02/27/2021 9:26 pm
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Pillar of the Community
Canada
6244 Posts |
In fact the "copper" penny is tombac. In that year was 95% copper and 5% zinc. This alloy is tombac.
quote: "modern enamel tombac or emailer tombac - an alloy of 95% copper and 5% zinc, suitable for enameling, therefore the name".
Probably the coin was clean with some kind of acid and come back to the melt state colour.
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Valued Member
United States
82 Posts |
Sorry y'all I'm trying to keep y'all up dated on the status of getting my coin scale back so I can post the right weight but things have not been the smoothest at home roommate can't drive any more bc he was busted driving with out a license and we had to spend somewhere near 700 to get it out of impound and my buddy wills car is still trashed from this winter when he slid Into a curb and broke his front right axle and now his car will not stay straight on the road soo his car is out my roommate can't drive my grandmother can't drive I don't have a license and my scale is in another town as soon literaly as soon as I get the scale I will posts the weight of the 1970-D penny that looks like some kind of acid damage with heavy scrubbing
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Pillar of the Community
United States
4406 Posts |
Quote:
modern enamel tombac Enamel? That's not what coins are made of at all. Tombac for coins has a higher zinc content. For example, the Canadian nickels of 1942-1943 that were Tombac were 88% copper and 12% zinc. According to Wikipedia (where Silvio got his quote) the correct name for the US cent's 95/5 alloy is "Gilding Metal". But that's unrelated to the original question anyways. I agree that this coin appears like some sort of environmental damage, some chemical reaction discolored the coin, then it was either cleaned or worn down by circulation. Edited by Tanman2001
03/09/2021 09:25 am
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Bedrock of the Community
United States
62064 Posts |
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Valued Member
United States
82 Posts |
I finely have my scale back here is the weight of the 1970 d penny  |
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Pillar of the Community
United States
1658 Posts |
Just slightly underweight, supports the acid damage.
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Pillar of the Community
Canada
6244 Posts |
@ Tanman2001.
Your name of gliding metal is the old name for this kind of tombac. Even the what you look ( Wikipedia ) will give you same name like the alloys metallurgical books "enameled tombac" which are use today.
Your old name and the modern name are synonyms. Personally I use the last names but accept the old also because is hard to change people to the new nomenclature.
I give you here the specs of this alloy (you can check if I am wright):
ASTM B36, a cold roll alloy, yield 50Ksi, tensile strength 56Ksi, elongation on 2 inch 5%, hardness (Brinell scale)114
Hope at your satisfaction
Silvio
PS the wright way to say on collecting will be just: tombac, brass and bronze.
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Replies: 19 / Views: 7,073 |
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First Page
Posted 02/14/2021 10:56 am
