I tried mica powder in Alumilite White once, hoping to add some sparkle to the dyed colors, but in the end, I couldn't tell it was there.
It will show. It requires a higher load ratio, and it doesn't stand out like using it in clear, depending on the color. If you dyed it another color, that too will affect the outcome.
Using Alumilite white, isn't much different than creating an opaque white(or any other opaque color) with PR, and adding Pearl-X.
The sparkle will show, not necessarily the color of the sparkle.
When pearls are added to paint (i.e. auto), there is sparkle but, if the pearl is added to the clear, there is color and sparkle. It has to do with light transmission, refraction, and reflection. A clear medium allows these, where and opaque medium affects them.
Some of the really nice, high end paint jobs, utilize a mid-coat to suspend the pearls. It makes the color really pop, and adds dimension. The same happens with resin.