Formation of magnetite within the droplet phase of immiscible glass

An immiscible glass system consisting of a continuous silica-rich phase and a discontinuous droplet phase enriched in phosphorus form the glassy framework for a novel magnetite glass-ceramic. Upon cooling from the molten state, the material phase separates into the droplet-in-matrix structure and magnetite precipitates spontaneously within the phosphorus-enriched droplet phase. Magnetic hysteresis curves of an exemplary magnetite glass-ceramic show a saturation magnetization of ∼20 emu/g and magnetic remanence of 2.6 emu/g for a maximum externally applied field of 30 kOe. This novel material space provides a simple and economical means to produce magnetite glass-ceramics with potential suitability for a variety of biomedical applications.