The creation of a trillion dollar platinum coin was suggested as a possible way to circumvent the debt ceiling in 2013. The U.S. government could cash in the coin to help pay down the nation's $16.4 trillion debt. The federal government hit its legal borrowing limit of $16.394 trillion on Dec. 31, 2012 and began taking "extraordinary measures" to cover shortfalls. It was estimated that, if left unaddressed, there would likely would be less revenue coming in than had to be paid out for each of the days between Feb. 15 and March 15 of 2013.
The first mention of the trillion dollar coin idea has been attributed to a commenter and blogger on economics and politics blogs whose screen name is Beowulf. His first comment on Platinum Coin Seigniorage was on a site run by Brad Delong. Anonymous commenters helped spread the concept to other economics blogs. The idea attracted attention from prominent liberal economists such as James Galbraith and Paul Krugman, and then from writers like Matthew Yglesias and Ezra Klein. 
Based on the authority granted by Section 5112 of Title 31 of the United States Code (31 U.S.C. Section 5112), the U.S. Treasury secretary is legally permitted to mint platinum coins of any level he or she wishes. The law was intended to allow the production of commemorative coins for collectors.
A petition at whitehouse.gov asked the U.S. Mint to make the coin.
While some claimed that minting such a coin would make the U.S. monetary and political system look like a farce, most were hard pressed to come up with a reason - legal or economic - that the coin should not be created.
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