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Precipitation behaviour of commercially available pure aluminium with trace impurities throughout repeated melting has been carried out. Cold rolled alloy samples are isochronally aged for 60 minutes at different temperatures. Isothermal ageing is carried out at 250ºC temperatures of cold rolled samples for different time up to 240 minutes. Hardness values of the aged alloys have been measured to comprehend the precipitation behaviour of the alloys with trace impurities. Trace impurities causes small age hardening effect as well as they pin moving grain boundaries and inhibit grain growth. The kinetics of precipitation of metastable phase in trace added alloys are found to be controlled by the diffusion of GP zones in aluminium. The results of this study confirmed a positive influence of alloy remelting upon the material properties and structure. The SEM images of fracture surfaces show spherical “dimples” correspond to microvoids that initiate crack formation and with the increasing of impurities the dimples of the fracture surfaces ever more decrease and become shallower.