Why Are Judaea Capta Denarii So Expensive?

Well it would be nice if this was true: The coin is special because in Isaiah 3:26 back in the 8th-7th century BC he has a vision for the fall of Jerusalem and from the King James Version of the Bible "Her gates shall lament and mourn, And she being desolate shall sit on the ground." So he has a vision but what is a vision except for seeing future events right? So in his mind he sees Jerusalem after Vespasian and Titus are done with it and looking around he sees a lot of future Roman soldiers spending money which on closer inspection indeed has her sitting on the ground. Does seem a bit odd the coin kind of matches so well to what he was seeing.(Obviously that is not at all true but still kind of cool. I am not sure the Tribute penny of Tiberius is that rare either but it certainly commands some money to get one.

"Value" is a product of supply and demand. These are valuable because even though the supply is relatively high, the demand for these coins is much higher than for other equally common coins, and this in turn is due to their inclusion in most "biblical coins" lists.

In that sense, they are "more valuable than they ought to be" for much the same reason that coins of Hawaii, Puerto Rico and US Philippines are more valuable than they ought to be: they are more in demand, because they are listed in a popular book (the Red Book) that many collectors use as their guide for "what to collect".