Starting in Release 61, we will be simplifying the crowns to simply be crowns rather than a specific metal type. No action is required by players and we will migrate these all during our Release 61 update window when the servers are down. For example, if you now have 23 gold crown and 7 iron crowns, you will simply have 30 crowns after the migration. If you have crowns placed as decos, they will simply look like gold crown after the migration. Going forward, all Obsidian potions will simple cost a crown vs a specific crown metal type.