So the few friends I do have always let me go through their change before cashing it in..I came across this dark red penny. Ive never seen a coin turn red like this before.. I tried looking it up but all I can find is when someone says "red" it means it's in perfect condition! This is clearly not that! Can anyone tell me more about this..if it's an error or if it's from being in circulation..
That kind of red is from some sort of environmental damage. The coin has been in some kind of damp or acidic environment.
was in the ground - a lot of coins get dark sitting in the ground here is an example of some coins I found in the ground being dark
I find coins like that metal detecting all the time. When the copper coin is buried in the soil for a period of time, the copper oxidizes to that "red" color for the cents. The ones minted after 1982 are mostly zinc with about 2.5% copper so they usually show zinc rot (corrosion) instead of the red color. It depends on how acidic or alkaline the soil is as to how the coin looks when it comes out of the ground.
Even though the coin has the appearance of red it’s actually brown. It just looks red due to environmental damage since it’s mostly copper.
Copper(I) oxide or cuprous oxide with the formula Cu2O is what that is, it's toning. this type of toning happens in a water environment containing acid. A pool, a fountain, acidic damp soil, something like that, and in there for a while but not long enough to corrode. if it were air, it would turn eventually green like the statue of liberty. that's Copper Oxide (CuO). Copper(II) oxide or cupric oxide is black, this is tenorite, and caused by fire. So, copper, if mostly dry and not put in a fire, goes from shiny copper to dark brown and eventually to green from the air. if submerged, it goes brown to red. if burned from 500-1500 degrees F, it goes brown to black. the red can happen to dug coins, in wet, acidic soils also, doesn't need to be a pool or fountain or involve chlorine which does turn metals black (terminal toning) , but it does need the wet acidic environment to get the red color.
The statue of liberty is green through reaction with substances in the air other than oxygen. Oxides of copper are either red, yellow or black.
If you look at a color chart of cents, it’s brown. So what I’m saying is it looks red because of the environment. It’s not red due to manufacture as it should be.
That penny looks as if it was fairly new, then lost in the ground for a while, recovered at some point and then cleaned.
