You joke but it's interesting to think about what mixing them or mixing their components would do. Mixing them as-is would ruin the effect of Vantablack. Since

You joke but it's interesting to think about what mixing them or mixing their components would do. Mixing them as-is would ruin the effect of Vantablack. Since carbon nanotubes are black you probably would get a boring grey color with a gloss surface due to barium sulfate. I'm curious what the effect would be if you coated Vantablack with barium sulfate. A highly reflective surface with an extreme black paint underneath.