Molecular surface of Vitamin B12. "Vitamin B12, vitamin B12 or vitamin B-12, also called cobalamin, is a water-soluble vitamin with a key role in the normal functioning of the brain and nervous system, and for the formation of blood. It is one of the eight B vitamins." --http://en.wikipedia.org/wiki/Vitamin_B12 Images of B12 in stick form are shown for reference. Model created using VMD: http://www.ks.uiuc.edu/Research/vmd/Successfully printed by a Replicator 2 in PLA using MakerWare(TM) 2.2.2.89, standard resolution (3 shells, 25% infill), with raft and supports. Different representations are provided as a guide to coloring the molecule by hand.