Just the other day I downloaded origin and SimCity onto my Mac mini. I have the model from 2011 with an
Intel HD 3000 graphics chip and an i5 processor. I have 5 gigs of ram in mine, but I'm actually not sure at what point the game starts complaining about that. If you had 4 or more, I don't think ram would ever be the limiting factor.
It does run, but the lighting effects do not work well. I have two monitors connected, one at 1600x900 and the other at 1440x900 and I run SimCity in a window at 1366x768. It's not optimal, but it does work about as well as it does on my PC with similar hardware.
HD 4000 on the 2012 mini should be even better, and if you happened to be able to get your hands on the 2011 mini with discrete graphics, that may be slightly better yet, although a 2013 mini with IRIS Pro graphics (if Apple were to be so kind to us) would be even better than that.