Sales platforms, grading, and auction venues all influence a coin’s price—but how much? A closer look at the key-date 1934 Irish florin reveals the challenges of accurate valuation.

A coin can be worth a ton of money -- a pretty penny, one might say -- if it's rare and has enough historical significance.

Numerous attempts have been made to reliably estimate the number of coins of a type or from a specific die minted because mint records if they ever existed, have not survived.