Remanent magnetization of a “paramagnetic” composition in the ilmenite‐hematite solid solution series

In the ilmenite‐hematite solid solution series, compositions more ilmenite‐rich than Ilm 73 Hem 27 are classically thought to be paramagnetic at room temperature. We have, however, synthesized Ilm 80 Hem 20 samples that acquire hard saturation remanent and thermoremanent moments. From analysis of AC demagnetization data, the source of the measured remanence is believed to be a single‐domain (SD) like material within the Ilm 80 Hem 20 grains themselves. On the basis of transmission electron microscope observations, we suggest that transformation‐ induced domain boundaries, which in part are enriched in hematite component relative to the bulk composition of the grains, could act as the magnetic carrier of the SD‐like remanence.