Why are dimes so small?

Dimes are worth more than nickles or pennies, yet are smaller than them. How come the sizes of coins are not in relation to their value?

From the U.S. Mint:

Basically, dimes are still the same size as they were when they were silver (even though they haven’t actually been made out of silver in years). Nickels and pennies, on the other hand, were made out of “base” metals even back when other coins (dimes and quarters on up) were made out of precious metals. Note that nickels and pennies don’t have the ridged edges that dimes or quarters do; those were originally to prevent people from shaving off a little of the silver, which no one would bother to do with a coin made of copper or nickel.

dimes, quarters, half dollars, and dollars were all originally made only of silver. I believe the price of silver was set by the government (WAG). Anyway, $1 worth of silver was found in a dollar, a fifty cent piece was half the weight of a dollar, and a dime contained 1/10th the weight of a dollar. A nickle and a penny don’t contain silver so they do not follow the scheme. Now, of course, the “silver” coins are not all silver, but in order to preserve continuity, the sizes all remained the same… Also I’m referring to the dollars up to and including the Eisenhower dollars…Someone got some courage somewhere and made the new dollars a different size

Actually, for most of the time while U.S. coins were still being made out of silver, the silver in them was worth a lot less than the coins themselves. I have a 1960 edition of The World Book which says that the silver in a dime was only worth about three-and-a-half cents. This only changed a few years later, when general, chronic inflation kicked in and the price of silver rose sharply. This resulted in silver coinage being mostly discontinued in 1964.

“Free silver” advocates in the 19th century wanted “free coinage” of silver, which basically meant that if you brought the Mint a dollar’s weight of silver, they would make it into a dollar for you. If the silver was only actually worth 35 or 50 cents, then that represented quite a nice profit for you. So obviously people with silver interests were very much in favor of this idea, but others countered that such a policy would be inflationary. Which of course it would…just like printing more paper dollars.