Are 1974 and 1975 pennies made of a different composition?

[Ecotic]

So I'm on my third month now in the penny sorting hobby, and after about 1,000+ pounds of copper pennies I have a small stack of 1974 and 1975 pennies which fall in the reject slot of my Ryedale every single time. It's just those two dates, and only about a dozen such pennies. But it's awfully strange to me as to why they're constantly rejected. The first time it happened I thought I had a rare or unique composition penny, but then I found more like them. Obviously the vast majority of 1974s and 1975s that I've found didn't fall in the reject slot, so it's just a very small percentage that will potentially be rejected, I think.

Anyone know why or have any good insights?

[uthminsta]

Hmmm... a slight inconsistency in the metallic content during those 2 years is not unthinkable. I have found ONE copper cent that consistently falls as zinc... and it's a 1975. A slight difference in its signature going through the comparator is the only reason I can think of. I mentioned it here, with some humorous responses.
viewtopic.php?f=21&t=12242

Hey, if you pack a 74 P, D, and S in an envelope (or whichever mints you have) I will give you a buck to cover your postage and your trouble.

[Ecotic]

Well how about that?! We've discovered a pattern. My only guess then is the usual 5% zinc admix got slightly changed in a few pennies in 1974 and 1975 that caused them to be rejected like some old wheats.

But hmm, let me think about whether I can part with my special pre-82 rejects. They might have numismatic value, or just a fun novelty factor. I want to weigh them for example when I get an accurate scale, and see if they're even copper or maybe "trial" compositions that escaped the mint.

[uthminsta]

That's understandable. I'm just interested in any oddities from the year I was born!

[DebtFreeMe]

I've noticed the same with both of my machines, one being a Ryedale, that those years will often seem to be rejected. I was wondering if there was actually something to it, or if I was just noticing it because I was thought I could see a pattern.

[CardsNCoins]

I find a lot of 1941s on the reject side.

[Ryedale]

Since starting years ago with the coin comparators, i've found many 1974's and 75's that are rejected. I'd like to XRF a few of them to see the actual metal breakdown.

[tedandcam]

Since starting years ago with the coin comparators, i've found many 1974's and 75's that are rejected. I'd like to XRF a few of them to see the actual metal breakdown.

Andy, contact Market Harmony.... I'm pretty sure he has the equiptment to let you know

[mitsuki3]

So I'm on my third month now in the penny sorting hobby, and after about 1,000+ pounds of copper pennies I have a small stack of 1974 and 1975 pennies which fall in the reject slot of my Ryedale every single time. It's just those two dates, and only about a dozen such pennies. But it's awfully strange to me as to why they're constantly rejected. The first time it happened I thought I had a rare or unique composition penny, but then I found more like them. Obviously the vast majority of 1974s and 1975s that I've found didn't fall in the reject slot, so it's just a very small percentage that will potentially be rejected, I think.

Anyone know why or have any good insights?

Both '74s and '75s are 97.5% copper and 2.75% zinc. Same with ALL pennies up to 1981 and most pennies from 1982.

[Z00]

I am going to shut my mouth and let someone else educate the last poster. I wouldn't know how to start.

[68Camaro]

Likewise - I've noticed mid-70s getting sometimes rejected. 74-76. They seem to be borderline. Sometimes they will go through on copper side and then go to zinc on the second pass.

[jasmatk]

So I'm on my third month now in the penny sorting hobby, and after about 1,000+ pounds of copper pennies I have a small stack of 1974 and 1975 pennies which fall in the reject slot of my Ryedale every single time. It's just those two dates, and only about a dozen such pennies. But it's awfully strange to me as to why they're constantly rejected. The first time it happened I thought I had a rare or unique composition penny, but then I found more like them. Obviously the vast majority of 1974s and 1975s that I've found didn't fall in the reject slot, so it's just a very small percentage that will potentially be rejected, I think.

Anyone know why or have any good insights?

Both '74s and '75s are 97.5% copper and 2.75% zinc. Same with ALL pennies up to 1981 and most pennies from 1982.

I think its more like 95% copper 5% zinc

[mtldealer]

Since starting years ago with the coin comparators, i've found many 1974's and 75's that are rejected. I'd like to XRF a few of them to see the actual metal breakdown.

I'll see if I have any of the "rejected" copper coins and test them over the weekend with a XRF. I'll post them Mon when I get back to my office.

[penny pretty]

interesting. in my last post, jackpot, I came across 24 rolls of CWRs that were all copper, and 1975 was the newest date. no order to them, but had about 300 BU 75 and50 74. maybe a blind rydale operator? if anyone needs BU 75 let me know, these are PERFECT! dont know the market, but 1st 5 that PM me and send a SASE Ill send ya one back free.

[VWBEAMER]

I had had a few 1974s and 1975s that got rejected every time. whether I was running cooper accept or zinc accept. BTW, not all 1974 and 75s are this way.

i think I made a post about, weighed it, did a google search. IIRC, there was some pennies in the mid 70's made from experimental metals, but the weighed a lot less than the copper ones. The ones i had all weighed around the same as a normal copper penny. In the end I figured some batch of pennies had a slightly different composition.


.

[VWBEAMER]

No, that is what the mint says they are made of, obviously if they are getting rejected then composition is different.

Both '74s and '75s are 97.5% copper and 2.75% zinc. Same with ALL pennies up to 1981 and most pennies from 1982.

[cesariojpn]

http://en.wikipedia.org/wiki/1974_alumi ... r_examples

Other examples

Several other related examples are alleged to have existed at some point or another, including

10 examples of a 1974-D aluminium cent, produced at the Denver Mint.[15]
Examples produced in bronze-clad steel.[4][5]
66 Aluminium cents made in 1975 as trial strikings.[16][17]
Nonsense description trial strikings of various compositions.[1]

[uthminsta]

Bump, to put this alongside the new thread with the video.

[slickeast]

Maybe the 74's are aluminum. Don't let the secret service know you have them.

Looks like someone in this thread has a penny that has a combined metal content of 100.25%

[uthminsta]

I found a 74 plain that falls zinc tonight. Among other really cool finds from the last couple days. So are those others all Philadelphia strikes?