https://www.cs.cmu.edu/~kmcrane/Projects/RestingBodies/Putti... That is the paper you want, it's about more shapes then just coins but you can special case it to a coin.
https://www.cs.cmu.edu/~kmcrane/Projects/RestingBodies/Putti... That is the paper you want, it's about more shapes then just coins but you can special case it to a coin.