High-quality single crystals of the magnetically dilute kagome staircase system (Co(1-x)Mgx)(3)V2O8 (x=0.029(3) and x=0.194(4)) have been grown by the optical floating zone technique. A pure Co3V2O8 single crystal was used as seed material in the growth process. The crystals obtained were characterized by X-ray diffraction (XRD) and refined in space group Cmca. Single crystal refinement shows preferential substitution of the Mg ions at the Co(2) site. Magnetization measurements show a drastic suppression of the ferromagnetic transition temperature of T=6.1 K observed in the pure material, attributed to the dilution with non-magnetic Mg ions. (C) 2011 Elsevier B.V. All rights reserved.