  Lattice spin, in planar condensed matter system with emergent Dirac
dispersion, is shown to emerge from the inherent SU(2) symmetry, arising
through Schwingers angular momentum construction from anti-commuting Heisenberg
operators of the sub-lattices. The presence of a mass term in the emergent
Dirac dispersion is essential for the existence of this spin. The usual hopping
term, that entangles the two sub-lattices, leads to the orbital counterpart.
Relative sub-lattice displacements, that couple to the effective Dirac fermions
like U(1) gauge fields, do not effect the lattice spin.
