Weigh it. A copper penny will weigh approximately 3.1 grams while a zinc one will only weigh around 2.5 grams. I can tell by your picture that the coin you have is almost 100% zinc. It lacks the depth that most copper cents have. Also, the odds of finding a copper 1983 error cent are extremely low.
Ok didnt know it had to be copper for brass color i was going by old article i guess should i have said plated? 1983, 1985-D, 1997, 1997-D & 1998 "Brass Plated"
Assume you're talking about the copper plating having some zinc in it. During early zinc cent production, there was a problem with zinc blanks coming loose in the plating bath and dissolving into the solution. Depending on how much zinc was dissolved, the plating could be considered brass instead of copper. However, you need to do a chemical analysis to show that there is zinc in the copper. First non destructive tests like XRF (with lab grade equipment) or SEM/EDS aren't cheap. In addition, these tests penetrate slightly below the surface. Usually, this isn't a problem, but the plated layers are very thin and directly underneath is lots of zinc, so if you get a reading of 10% Zn, is that from the coating or are you starting to pick up the Zn core? FWIW: I don't think yours is brass, I have some that are a lot more yellowish that I picked from change in the 80's. I'm certain they're brass (I've spent my career working in Material Science/Engineering), but without analytical data it's just my opinion and color alone isn't a reliable indicator.
? I have no clue what you're asking. Isn't this thread about the valuable 1983 3.1 gram copper cent? What do you mean by brass? In 1983, all cents were supposed to be made of zinc with a thin layer of copper. A very small amount of old 95% copper planchets accidentally made their way into production in 1983 and were minted as 1983 cents. These are worth a considerable amount of money. As for the "brass" coins you are talking about... I have no idea.
I gave Oldhoopster a best answer for his post, he is spot on. Brass is an alloy of copper and zinc, bronze is an alloy of copper and tin, with other impurities as well. The specific alloys for copper and copper plated zinc cents can be found in any copy of Yeoman's Red Book, by year and design variance. Or you could search the web. What I take away from OldHoopster's post is that your yellow, brassy looking 1983 cent probably spent time in a copper plating bath that had substantial zinc dissolved in it, meaning the bath was used beyond proscribed limits. Also cogent is his info on the expense and difficulty in determining the brass content. Keep in mind that, in World War 2, recovered/recycled ammunition brass casings were reused to produce coinage. Once again, R.S. Yeoman's Red Book has data on the years it happened. Spark
