We have synthesised a novel material IrSr2Sm1.15Ce0.85Cu2O10 . Preliminary magnetic measurements evidence two magnetic transitions at Tc = 125 K and TM2= 6 K. Above Tc however there is still divergence of zero field cooled and field cooled susceptibility which suggests the presence of magnetic clusters. The susceptibility of IrSr2Sm1.15Ce0.85Cu2O10 is characteristic of a re-entrant spin glass. In a re-entrant spin glass at TCF magnetic clusters are formed in the material¿s otherwise paramagnetic state, as the temperature is lowered to Tc or TN, magnetic order is observed followed by a spin glass transition at TM2. We propose to record variable temperature neutron diffraction patterns of IrSr2154Sm1.15Ce0.85Cu2O10 between 400 K and 2 K in order to analyse the diffuse scattering of the magnetic clusters below TCF and to determine the magnetic structure below 125 K.