So I found out that there is a Giant Penny in the Batcave.

I wondered what it’s specs are.

In this picture, Bruce Wayne and Alfred are moving the Penny into the Batcave. Bruce has his knees bent, so if he were standing up, he would be about half it’s height. Which means that Bruce Wayne’s height is the Penny’s radius. The same DC wiki tells me that Bruce Wayne is 6 foot 2, or 1.87 meters. That means that the penny has a diameter of 3.74 meters, or 12.2 feet. That’s 1.2 stories tall. The thickness then extrapolates to 0.30 meters, because a regular penny is 1.55 mm thick. The volume of the penny is then 3.29 m^3 by \(v=\pi r^2h\).

The penny has the date “1945” on it, so i looked up what the composition of an American penny was in 1945. In 1944-1946, American pennies were brass, 95% copper and 5% zinc. That means that for a total volume of 3.29 m^3, there are 3.12 m^3 of copper, and 0.16 m^3 of zinc. Then, we need the density of each element. The density of copper is 8.96 g/cm^3. The density of zinc is 7.14 g/cm^3. Re-arranging the density equation from \(d=\frac{m}{v}\) to \(m=dv\), we get that there are 27,955,200 grams of copper and 1,142,400 grams of zinc. This gives a combined total of 29,097,600 grams of penny, or 29,097 kilograms, or 64,149 pounds.

This penny weighs 32 tons (short tons). The world record for Olympic Weightlifting belongs to Hossein Rezazadeh, from Iran, for lifting a total of 472 kg, or 1,048 lbs. To lift this penny, we would need 61 Hossein Rezazadehs. Unfortunately, this means that Bruce Wayne and Alfred would become flat trying to haul it into the Batcave.

The wiki page says the penny makes it’s first appearance in 1947. I can’t find the value of copper or zinc in 1947. The wiki does say that the penny’s last appearance was in April 2007, so we’ll use the prices from then. On April 7th, 2007, copper was worth about 3.39 USD/pound. Zinc was worth 1.58 USD/pound. Therefore, in 2007, Batman’s giant, 32-ton penny is worth $212,907.

Unfortunately, the DC Wiki tells me that in the 2007 issue, “Brave and the Bold (Volume 3) #1”, the giant penny is destroyed.

Sorry Batman, i’m sure that you have wealth tied up in plenty of other places, other than in a 32-ton penny.