mica + -aceous. From Latinmīca ("grain, crumb"). Often erroneously associated with Latin micŠ("to twinkle, glitter") and hence with English micacious.
Full definition of micaceous
Adjective
micaceous
Of, pertaining to, consisting of, containing or resembling mica.
(figuratively) sparkling; brilliantThe book review was a micaceous example of perfection.