How Quarters Are Made By Mark Hilton and Adam Ziegler

History of the quarter  The U.S. mint selected the quarter to be a main U.S. coin, in 1793  Quarter production stops and starts throughout the late 1700’s and early 1800’s. The design changes several times.  Around the 1830’s, new steam power minting equipment was invented.  By 1932, the modern quarter design came around, with a picture of George Washington, replacing Lady Liberty.  In 1999, the 50 state quarter program began.

Mining First, miners mine the nickel and copper ore out of the ground. Then, the chunks of ore are broken into smaller pieces and prepared for metal processing.

Metal Processing  After being mined, the raw ore needs to be processed into pure metal.  The ore is put into a solution that dissolves the ore and removes impurities.  Another chemical is added, which turns the dissolved ore into pure metal.  The metal is then melted down to the proper size and shape.  The metal in quarters is a combination of 91% copper and 8% nickel. The metal is formed into long, coiled sheets that are 13 inches wide and 1500 inches long.

Quarter making: Step 1 The coiled sheets are delivered to the mint, where they are unrolled. A machine called a blanking press cuts out round discs called blanks. The excess metal is recycled.

Quarter making: Step 2 The blanks are heated and washed to soften them. The heating process is called annealing.

Quarter making: Step 3  The good blanks go through a special mill called an upsetting mill. This puts the ridged edge on.

Quarter making: Step 4 The blanks go to the coining press. They are stamped with the designs and inscriptions that makes them U.S. coins. For quarters, the blanks would be stamped with the bust of George Washington on the front, and the U.S. eagle or a state quarter design.

Quarter making: Step 5 Operators inspect each batch of coins with magnifying glasses.

Coin making: Step 6 An counting machine counts the coins and drops them into large bags. The bags are sealed shut and taken to vaults. The bags are then taken to federal reserve banks, which in turn send them to local banks, where they begin to be used.

Sources  U.S. Mint. oins/ oins/ oins/  Copper mining and processing. engineer.com/mining/copperm.htm engineer.com/mining/copperm.htm engineer.com/mining/copperm.htm  Timeline of U.S. quarters. tml tml tml