Metallic inks quality control.

Dear all, I am wondering how to deal with the metallic inks quality control. As far as I know, it seems impossible to use a conventional spectrophotometer due to their own specific reflectance. So, I’m guessing we need a tool able to measure in multiple viewing angles. But is it feasible in the same manner like automotive exteriors? And if so, what are the tolerances we need to achieve if any existed? Thank you for your clever explanations. Regards. Axel Robert | Prepress Manager UBISOFT |EMEA Manufacturing