What peso coin is rare?

Have you ever come across a rare peso coin in your collection or during your travels? If so, which one stands out as particularly scarce? Are there any specific years, mint marks, or other identifying features that make certain peso coins more elusive than others? As a cryptocurrency and finance professional, you might not typically deal with physical currency, but for those interested in numismatics, the pursuit of rare coins can be just as thrilling as investing in digital assets. So, which peso coin do experts and enthusiasts alike consider to be the holy grail of the currency world?