My cousin and I were reminiscing about old times earlier today. Well,he brings up this one time that his family came down to visit my family when we were kids,we hardly ever saw each other because we lived about 400 miles apart.

I am about 7 years older than him and was usually the instigator of our youth-fueled shennanigans. Ok. A few weeks back my Dad brought over this little Bandito welder set(you know,the small ones that have the 2 foot tall tanks),I don'tknow what the real name of the set is. So we broke it out and started melting stuff like tin and aluminum cans,my sister's Barbie dolls,whatever.
So then I reach into my pocket and grab a penny to melt and lay it on the sidewalk. We start ooohhg and aaahhing as it starts to turn all these puuurty colors and all of a sudden:POW! the thing blows up!
Luckily my cousin was wearing glasses! you could see little pieces of copper(?) embedded in the lenses(these were really,really tiny pieces and they just blew off with a firm breath). That was about it,other than the slight stinging we got on our faces from the molten metal.
All these years I thought it blew because we got the concrete hot. Could it have been because the penny was not pure copper? The reason I ask is because I've always kept a huge coin jar,but only put in the "silver"coins in it(nickels,dimes quarters). Now I want to collect only all-copper pennies also.
So what year did they stop making all-copper pennies?

Thanks,
Ray IV

1981 IIRC - and some of the pennies issued that year were all copper, and some copper plated zinc.

Yep 1982 first year for all pennies to be plated zinc

The concrete blew up showering you with you molten (zinc) penny. Never weld on concrete or run a torch on it as it will pop itself loose with an impressive amount of force.

I used to GTAW the pre 82 pennies into doodads.

Dang Troy! pretty impressive list! do you clooect coins? Thanks everybody else,too. You know Sirious1,that was the first and last time that I have ever welded on concrete. Before that,I would just use the vice on the work-bench,and play around with it.

Quoted: Yep 1982 first year for all pennies to be plated zinc

That required it but not all the mints were up and running in time.

You will find 82 pennies in both copper coated zinc as well as solid copper, think there were a total of 4 variants.


You can hear the difference if you try to get a penny to resonate.   If you flick it up in the air with your finger nail you'll hear a solid copper penny resonate(same with silver coins), same if it drops onto the counter to bounce or spin around.   Will have a distinct ringing sound.

The clad coins with zinc/copper will sound dull or "thud" by comparison.


Other way would be to weigh it but the quick and simple method, unless you're talking about a true collectable coin, is to get it to resonate.

I collected coins when I was a kid.  I remember have an 1864 indian penny that was bronze like most of the early ones.

www.coinflation.com/

All we ever did was put pennies on the train tracks.

Lucky for us we never derailed one.