I've found pennies that appeared to be zinc but when I flipped them over they were 1981 or older. All of them I've found have been late '70s or early '80s. I've never seen a penny from before 1976 or so that looks like these did. Is it possible that a few zinc pennies were let into circulation to test the composition before switching over? Or is it possible that some test coins were accidentally leaked into circulation?
You probably found some cents that were plated in zinc or some other similar element. It was popular to use cents in school science experiments back then due to the high copper content of the coins.
Since the zinc cent outer layer is 100 per cent copper rather than 95 % solid, a spectroscope could distinguish without harming the coin, but I doubt it also.
VERY unlikely but if you still think you got something, just weigh them on a gram scale. If its around 2.6 grams, its zinc. If its around 3.1 grams, its copper. Allow .1 or .2 grams as a tolerance between metal loss and accuracy of the scale.
And be VERY careful. Cents having been dipped in mercury are not unusual. When the mercury gets "dirty" it can resemble zinc. And mercury is very toxic and is easily absorbed through the skin.
You hear that a lot, but I don't think I have seen a real mercury coated coin in the last 40 years. LOTS of zinc, nickel, chrome plated coins, but no Mercury coated. And while mercury can be very toxic, it doesn't absorb through the skin easily. The real danger is if it is vaporized and you breathe the fumes, or organo-mercuric compounds which don't really form that readily. I would recommend not eating it though.
when I was a kid we played with mercury didn't have seat belts no helmets when riding a bike could walk anywhere on and on those were the days
Well, that explains a lot.... /I did all that stuff too, plus we even played with toy guns (horrors!)
We played with "real" guns - bb guns and pellet guns. The air powered pellet guns hurt the most We never managed to shoot our eyes out fortunately.
Now if we held cellphones next to our head for almost our whole adolescence , think of how smart we would all be
I played with mercury a few times as a kid. Really weird stuff. We did a few coins. Sure made them shine. I always thought the mercury would just wear off the coin. What makes it stick to the coin so well?
Actually, today's youth lack when compared to our more barbarous upbringing. Goober protections and laws coddle the little guys. Bike helmets? Concussion issues with football? Who the devil knew? We all knew back then but we didn't make a big deal about it or a class action law suit..
I miss those days when being free was an American value, now if we want any privacy or free speech we're called "terrorists". My has America lost its way.
Mercury, being a liquid metal acts like many liquids and starts to dissolve solids. In this case it actually starts "melting" and alloying with the coinage metal forming an amalgam with the surface metal. And it will stay there unless enough heat is applied to vaporize the mercury.
That was why mercury was used in gold mining. For placer mining mercury would be put in the baffles of the sluice boxes. Its weight would keep it in place as the water flowed over it but as the gold dust and small flakes came into contact with it they would be attached and dissolved into the amalgam. With hard rock mining the rock would be crushed to a powder and mixed with the mercury. The mercury wouldn't attach to the rock but it would pickup any powdered gold released. (For even more complete gold recover the powder would be boiled in a sodium cyanide solution which leached the rest of the gold out of the rock.) When the amalgam has absorbed all the gold it can it would be taken away and heated to drive off the mercury leaving the gold behind. In large operations the mercury vapor would be condensed to recover the mercury for reuse. The small placer operations often just heated the amalgam in an open container and let the mercury escape (and were often poisoned by the mercury fumes)
