I was investigating what happens to acrylic paint when you add marble dust. I have used it cold wax and oil media, as well as printmaking inks, to stiffen the consistency of the material. So what happens if you work it into acrylic paint?
Looks like we've found a way to make transparent acrylics opaque without adding white, which changes their value.
From right: quinacridone magenta, manganese blue hue, Indian yellow hue, and quinacridone gold, each in their straight-up form and with marble dust added.
This is what I got from Blick.
At the top, the magenta and blue are opacified quinacridone magenta and manganese blue hue
At top on the left you see Indian yellow hue straight out of the bottle; to the right you see it with marble dust added.