I've calculated the six sides. The actual I've remembered now and found comes from 'A Brief History of Time' Chapter 4's particle-wave duality explanation and from 'A Brief History of Time', Chapter 5: Elementary Particles And The Forces Of Nature . . . section on particle appearances, appearances of differing particles, from the 'spin' of the particle, and the particle / anti-particle pairings. Also, the six flavors of quarks, ("which we call up, down, strange, charmed, bottom, and top.... Each flavor comes in three 'colors', red, green, and blue") -- Stephen Hawking from the book.
So, I suppose I am to be sledgehammered for finding what I wanted to find, but couldn't find the exact wording directly in the book (though I hit the exact wording in a search engine result)! I hit the exact wording in the search on the net for it ("In his book A Brief History of Time, Stephen Hawking describes a six-sided particle as having six different 'flavors' (up, down, strange, charm, bottom, and top) and three different 'colors' of quarks (red, green, and blue)").
The exact search wording was "Stephen Hawking's description of a six-sided particle from his book A Brief History of Time?" And the return quoted above was the immediate return from the AI.