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The age of the inner core nucleation is a first-order problem in the thermal evolution of the Earth that can be addressed with palaeomagnetism. We conducted a palaeointensity study on the 1.3 Ga Gardar basalts from southern Greenland to investigate previously reported high ancient geomagnetic field intensities. Biggin et al. used the earlier result to identify nucleation of Earth's solid inner core at 1.3 Ga. We collected 106 samples from 39 flows from the lavas of the Eriksfjord Formation, sampling 17 of the lower flows, 8 of the middle flows and 14 of the upper flows. Rock magnetic analyses, including magnetic hysteresis, first-order reversal curves and magnetic susceptibility versus temperature measurements, suggest that the predominate magnetic mineral in the lower basalts is low Ti titanomagnetite, whereas the middle and upper flows have varying amounts of hematite. The magnetic hysteresis data suggest …