Why is the US dime smaller than the US penny?

Answer 1

Because of what the coins were made out of. In fact, the penny used to be much larger, about the size of a half dollar! Early British pennies were even larger, weighing an ounce and being larger than a silver dollar! But the dime until 1965 was minted in 90% silver and the penny up to 1982 was minted in copper. Because copper was quite a bit more common and less expensive than silver, a copper coin had to be larger to have about 1 cent's worth of copper in it. On the other hand, 10 cents worth of silver (or close to it) was rather tiny. Thus the penny was large and the dime was small. Since the penny is no longer even made out of copper (it is now copper plated zinc) and the dime stopped being made out of silver a long time ago, today it is more of a curiosity. It is also for this reason that the nickel is larger than a dime, because the first 5 cent pieces were known as half dimes and were the same size as half a dime and were minted in silver. However, in 1866, the US government decided to strike 5 cent pieces out of 75% copper and 25% nickel (the same alloy used today) and because copper and nickel were more common than silver, the coin was increased in size to compensate for that.