Much like most people, I have a jar of pennies. A few years ago, I began separating my pennies and segregating them into two separate containers. One contains traditional pennies made of copper, and the other gets the new ones that are copper plated zinc. After hundreds of years of copper cents (ignoring the 1943 steel penny) they changed them in 1982 because pennies were worth more than a penny as scrap. Copper is currently around $4/lb, and zinc is around a buck. At $4/lb, a copper penny contains 2.8¢ of copper.
So I put on my reading glasses, and used a magnifying glass, to separate pre-1982 from post-1982 pennies. But what about 1982? The year was mixed. I collected the 1982’s in a separate pill bottle until it was full.
This evening I pulled out my great uncle’s jewelry balance (Today’s Object) and began comparing pairs of pennies. You see, copper weighs 8.9 times as much as water, and zinc only 7.1, a difference of 25%. Once I found a mismatched pair, I could compare the lighter one against each of the rest, and quickly separated the 1982’s into solid and copper plated. Most of the ones I had were solid copper.
Those solid ones I plan to keep around, and the plated ones get disposed of. It’s not because the older ones will get much more valuable any time soon. It’ll be generations before the supply of stashed copper pennies dwindles, even if they do manage to roll out the planned steel pennies or do away with them altogether. But they are a snapshot of my early life, and can always be turned into enough useful cash to buy a small meal.
There are several ways that I dispose of the zinc ones. The dominant and common way to to count and roll them and take them to the bank.
The second way is somewhat artistic. A few years ago I happened to have access to the freshly poured concrete alley behind my house:
The third is more fun and slightly dangerous. But this is the subject of my next post.