Rare coin worth an estimated $500,000 to be auctioned in October: What makes the dime so valuable?

In 1975, the San Fransisco Mint issued a set of proof coins, six of which were sold for $7.

A few years later, when it was reported that two of the dimes included in those proofs were missing the S to represent that they were minted in San Fransisco, a family in Ohio made an important purchase

The sisters, who have chosen to remain anonymous, inherited one of these dimes from their brother, reported the AP and in late October the coin is expected to sell for $500,000 at auction.

What makes the coin so valuable?

There are a few factors that drive up the price tag on this coin.

The first was that it was collectible from the jump. These coins were not in circulation and were instead sold by the San Fransisco Mint as collectibles. Secondly, the misprint only appearing on two dimes drives up the value massively for collectors. Plenty of misprinted coins are worth anywhere from a bit more than their exchange value to a couple of thousand dollars. In other words, the more rare the coin, the higher the price.

The AP also noted that in 2019, the other dime in this duo sold at auction for $497,000, and a few years later, the expected value went up to a few thousand dollars. As coins age, they become more valuable as there are fewer conditions that collectors would find acceptable. As the years pass and one of the two dimes is in much better condition than the other, the value of the two will begin to diverge as demand for the better-kept one grows.