can i use a ortofon black quintet mc cartridge with my mac mc 712 phono stage?

The C712 has a Phono Stage, designed for MM carts.       The Quintet Black is a Moving Coil, with too low an output (.3 mV), to work properly.       With an SUT: yes.         Otherwise: an external phono stage with enough gain for a LOMC cart, into the C217's AUX in.     

Get a Bellari SUT. Excellent SUT! I have one! Made in USA. Don't spend more!