Not just because of those objects - Theres a lot of people who got ahead stupidly fast because of the buff in iron prices. The economy is declining because people see high prices on cubits, mana, spawners, etc and expect to get high prices for other things as well. It's more or less that the economy has gotten bored of low prices and saw a chance to base for unnecessarily high prices, like 500m for a seller when i could just buy one off of the store for 18 dollars.