  Since
the minting of bronze coins over 2,000 years ago, copper has increasingly
become a preferred alloy in coins all around the world. From German
marks and U.S. quarters to British pounds, Russian kopeks, Chilean
pesos, and Venezuelan centimos, copper has enjoyed a major and permanent
market in coinage.
Over the years, copper coins have sometimes been minted in rather
unusual forms; take, for example, knife-shaped coins from the Qi province
of China minted in 350 BC; heavy rectangular copper plates used as
currency in Sweden in the 17th Century; X-shaped copper coins in what
is now Katanga; cast bronze coins with square holes from the Orient;
early 20th Century British brass farthings with blackened finishes;
and even 100-franc copper-nickel coins from the Congo Republic that
are highlighted with enamel inlays.
Last year, the USA began to circulate the new "state" quarters with
different reverse-side designs for each of the 50 states. Because
of the great popularity of these coins, the U.S. Mint now projects
production of over one billion coins of each state's design. That
adds up to over 50 billion quarters to be circulated in the next 10
years. Based on a weight of 5.67 grams of copper in each quarter,
a whopping 285,000 tons of copper will be required to mint these popular
coins.
Copper coinage is not just found in currency. Around the world,
hundreds of millions of copper-based tokens are used every day to
activate phones, vending machines, washer-dryers, and turnstiles for
rides on public transportation. |
