Adding Rainbows with pot of gold

I want to start by saying this idea should come with new items that utilise gold in more ways than currently available. After a rain event, there's should be a percentage chance, let's say 20% chance that after the rain has stopped, a rainbow visual will spawn along the edge of your rendered chunk size, this will always spawn a Full gold pot, basically a gold cauldron, the cauldron will have gold coins in it, and removing them creates an empty gold pot item.

The gold coins can also be made by placing 1 gold nugget into a crafting menu, breaking it into 4 gold coins which can be used to barter with piglins for a different trade table, or can be used with villagers for exclusive trade deals that you won't get with emeralds, though they will require a significant amount to overweigh the value of a single emerald. If this sounds good, you can even add a new mob or passive creature to coincide, The Leprechaun.