It would be nice, and might work in a pinch, but coloring white clay is not as simple as it seems.
The Hidden Feature in Translucent Polymer Clay - The Blue Bottle Tree
Polymer Clay Information and Tutorials - The Blue Bottle Tree
Polymer Clay Information and Tutorials - The Blue Bottle Tree
Evolution of a Design - The Blue Bottle Tree
Testing 41 Polymer Clay Sealers - The Blue Bottle Tree
Get Started with Polymer Clay - The Blue Bottle Tree
Making Watercolor Agate with Polymer Clay - The Blue Bottle Tree
Which is the clearest Translucent Polymer Clay? - The Blue Bottle Tree
Testing: Coloring Translucent Premo - The Blue Bottle Tree
Colored Translucent Polymer Clay - The Blue Bottle Tree
Polymer Clay Information and Tutorials - The Blue Bottle Tree
Storing polymer clay mixes the easy way - The Blue Bottle Tree
Evolution of a Design - The Blue Bottle Tree