According to the entry on copper in Scott Cunningham’s Encyclopeida of Crystal, Gem, and Metal Magic, copper can be used to draw money to a person.
To this end, he notes that United States copper pennies–especially those minted in leap years–have “long been place in the kitchen to attract money to the household.”
I think that’s a rather lovely idea. The kitchen is basically the modern day hearth–the place of home and of domestic prosperity–so it makes sense to focus some prosperity work here, and really, how much space or effort would it take to maintain a jar of copper leap year pennies in the kitchen?
I guess the biggest issue is knowing which pennies to save. According to the US mint, the metal content of pennies has changed historically. They were pure copper from 1793 to 1837. From 1837 to 1857, they were bronze (95% copper, 5% tin and zinc). From 1857 to about 1864, the pennies were 88% copper and 12% nickel (giving them a whitish appearance). They went back to the bronze (95% copper, 5% tin and zinc) between 1864 to 1962, with a year in 1943 where pennies were mostly minted in steel to direct copper to the war effort. In 1962, the bronze alloy changed to 95% copper and 5% zinc, and it remained that way until 1982 when the composition radically changed to 97.5% zinc and 2.5% copper.
So should you wish to take on this prosperity charm, you’ll have to content yourself with mostly copper pennies, seeing as you’d be darn lucky to find a pre-Lincoln penny in circulation these days. But from 1864 to 1982, the copper content was decent (excepting 1943). Seeing as it’ll probably be really rare to find a penny older than 1940, there’s only a handful of years to watch out for: 1940, 1944, 1948, 1952, 1956, 1960, 1964, 1968, 1972, 1976, and 1980.
If this is an idea that really floats your boat, I’d recommend writing these dates down on a card and slipping that into your wallet. Whenever you do your change purge, see if you’ve got any good pennies. Put them in your kitchen jar, then divert the rest to your “Coinstar” jar. After awhile, you’ll probably have a usable stash.