Why are copper silver and nickel used to make coins?

Answer 1

The choice of metals for minting coins is determined by a number of factors. Among the most important are:

• Cost
• Ease of striking
• Appearance
• Wear resistance

In the past, coins had to contain approximately their face value in metal. That is, a cent contained about 1 cent worth of metal, a half-dollar contained about 50 cents, etc. For that reason copper (an inexpensive metal) was used for low-denomination coins, while silver (a moderately valuable metal) was used for mid-value coins, and gold (an expensive metal) was used for high-value coins.

The three metals are relatively soft which made them easy to strike, although gold and silver are so soft that they usually had to be alloyed with a small amount of another metal to stand up to circulation wear. Finally, their obvious color differences made it easy to distinguish one coin from another even if they were similar in size.

It took a while for nickel to come into use. It's an ideal metal for coinage because in addition to being inexpensive it's hard and thus very wear-resistant. However it's so hard that it broke early coin presses. Hardened-steel dies were developed in the mid-19th century, allowing nickel to be used for regular circulating coinage. In the US, new denominations such as 3 and 5 cent coins were struck in a copper-nickel alloy and gained quick acceptance by the public.

During the 20th century gold and silver prices were deregulated due to increasing demand. That made the metals too expensive and the price too volatile to use in coins because among other things they became worth more as scrap metal than their face value. Most countries stopped making gold coins early in that century, and had to give up the use of silver by the 1960s. Nickel proved to be an excellent substitute because its color is only slightly darker than silver, allowing the familiar color differences to be maintained.

By the late 20th century many countries added new, higher-denomination coins to replace their wasteful low-value paper money. These coins are often made of a gold-colored brass alloy, echoing the old color relationships established centuries before.

Further rises in the cost of copper and nickel have now made even these metals too expensive for low-denomination coins so other metals such as zinc, steel, and aluminum are also being used.