Debate has existed for some time in the United States whether the penny should stop being minted, due to its small purchasing power and cost of production .
From what I understand, to discontinue its production would require direction from the federal government, since minting and circulating currency is a federal prerogative per the US Constitution Article 1 Section 8 :
To coin money, regulate the value thereof, and of foreign coin, and fix the standard of weights and measures;
Hypothetically, if a state or its citizens were bothered enough to take action, could a state legally implement a scheme where pennies were phased out of circulation (e.g. stored in a giant warehouse where they are no longer used after they are spent)? The state would still allow them to be used as legal tender, but once they are spent businesses would send them to storage.
(Ignore the practicality of this proposal, such as the expenses involved in transporting and storing all these pennies, why taxpayers would want to pay to remove a currency from circulation, etc. I'm only interested in the legal aspect)