The first 3D topological insulator to be realized experimentally was Bi 1 − x Sb x. Bismuth in its pure state, is a semimetal with a small electronic band gap. Using angle-resolved photoemission spectroscopy, and many other measurements, it was observed that Bi 1 − x Sb x alloy exhibits an odd surface state (SS) crossing between any pair of Kramers points and the bulk features massive Dirac fermions. Additionally, bulk Bi 1 − x Sb x has been predicted to have 3D Dirac particles. This prediction is of particular interest due to the observation of charge quantum Hall fractionalization in 2D graphene and pure bismuth.