Found in my car change cup--Large Copper or Large Brass?
sliderule
Posts: 15 ✭
Greetings.
I have a cup in my car into which I drop change that I receive. As I was cleaning it out I discovered what appeared to be a large copper cent--same diameter, about. Instead, it was a 20 Centavo Mexican coin from 1943. It appeared be copper and had a nice butternut tone, similar to some of the EAC coins from the 1840s and 1850s. (Sorry, I'll have to figure out how to get photos up here.) Obviously it has no numismatic value but it is a precious find--I wonder what story it could tell. How did it find its way to my small town?
I spent about an hour on the Internet on various sites and just can't figure out:
Is it bronze, not copper? If I (carefully) drop it and a cull EAC coin simultaneously form several inches onto my oak table, it makes a noise like a solid metal coin, not like one made of sandwiched layers. (However, it makes a higher-pitched "ping" than the EAC coin.) I couldn't find out for sure if it is brass or copper, and either way, the percentage of metals from which it it composed.
Does someone know its metal composition and--if the metal composition is the same for all the years of the coin.
On the EAC coins, the composition of the copper (mining impurities?) itself varies over the years (I think), making some planchets different than others. Do copper coins from other countries often have a different "purity" of copper due to different mining practices, location, etc. I have noticed that copper coins from around the world can have awesome differences in hues--perhaps this is from their combination into an alloy with other metals, or does the copper itself vary?
Any metallurgists here?
I could have kept going on the Internet for what the symbolism means on the coins--especially the mountain in the background. But perhaps someone can give us the full scoop.
It's a beautiful coin that I will treasure.
I've learned a lot from the site so I thought I'd join. My philosophy of collecting is simple: Follow the Caribou.
many thanks, "slide rule"
ANA, RCNA, MCC, NLG
Comments
The coin is made of 0.950 copper, 0.010 tin, 0.040 zinc. Tin was removed and replaced with zinc in 1951.
Many thanks for this info. This mixture makes a nice coin. best, SR
we need to hear what it sounds like dropped from a range of heights to make a full assessment