Based on the comment from Stephanie S on Google+, I have tried to work on another experiment with Graphite Powder.
So here was what I did:
During the mixing, there were some bubbles of “industrial” colour appeared… But the graphite powder are easier to mix with silicone in general (compared with the electrical paint)
And here’s the result:
So the result was… graphite powder + silicone = zero conductivity…