What would cause "wood grain" toning on a 1892 Liberty 5c ???

dizzyfoxx

I just picked up from my local coin shop a very pretty 1892 Liberty 5-cent in PCGS MS64 and in a first generation PCGS rattler holder. It has what I think is very attractive wood grain type toning in oranges and lime greens, a very attractive and unique looking coin. I'm wondering what elements of storage and/or environment would cause this style of toning? No pics yet, hopefully soon.

laserart

Do you suppose it could be a fingerprint?

WoodenJefferson

An improper mixing of the metals by the mint foundry (nickel 25% & copper75%) then rolled out to coining thickness. The streaks of different metal combination percentages tone differently over time.

robec

John, here's some woodgraining on a modern dime.

lordmarcovan

What WoodenJefferson said. Same thing that causes that look in copper coins. In nickels, the different particles of improperly-mixed alloy will tone differently, often with a pleasing effect like you've mentioned. I've seen it on other Liberty nickels.

Eagleguy

How about on a commemorative?


JH

Broadstruck

The one below isn't mine... here's my woodie





Here's another...