Received an inquiry about the above penny; was asked if coin would stick to a magnet. Was out of town and had to check coin before responding.
The coin sticks to a magnet, so it is steel. Now I did a bit of research also because it seems that various interesting things happened when the 1943 "steel" coins were minted. In 1943, all of the standard pennies were made of steel. This was done to save copper for the WWII effort.
This is where it gets a bit interesting. The typical steel penny started out looking like silver, but would go on to develop a dull grey appearance over time, if in circulation. All of these steel pennies will stick to a magnet.
Also in 1943, a few 1943 "Copper" pennies, made of copper-zinc-tin alloy, were also made. Most of these coins were reportedly found. There are only 40 known to exist; they are rare, and heavily counterfeited. If someone comes across a 1943 penny, that will not stick to a magnet, they need to have the coin certified, due to it's rarity and counterfeit potential.
Now, I have a 1943-D penny that sticks to a magnet. However, it is "copper" or "bronze" toned on the obverse (front), but it's reverse side (back) appears to be "steel" toned where the "copper" coloring has stripped away.
I had read that a few 1942 "bronze "planchets" (flat piece of metal stamped as a coin) were accidentally mixed in with the new "steel" planchets, and struck with the 1943 date, then released to the public.
So, the coin pictured above sticks to a magnet from the obverse and reverse sides, so it is made of steel. But it is "copper"/"bronze" in color.
Would appreciate any input from penny collectors or sellers as to your opinion about the above pictured penny. I will probably have it looked at by my local coin shop, or at a coin trade show. Thanks for any input.