Resumen
Information about the strategic mineral balance, published in 2013, presumed a significant amount of iron sand deposited in Sarmi, Papua, Indonesia. However, the magnetic properties of these iron sands have never been studied. Our preliminary study on the distribution of magnetic susceptibility of iron sand from the Sarmi Coast area has revealed that the iron sand from the Tor River estuary had the highest mass-specific magnetic susceptibility values with an ?LF average of 3.083 ×10-5 m3/kg. We extracted the raw sand from the Tor River estuary using a mechanical magnetic extraction method and analyzed the magnetic properties and mineral composition. The magnetic susceptibility values increased significantly with an ?LF average of 27.496 ×10-5 m3/kg. The chemical composition acquired from both the X-ray fluorescence and energy dispersive spectroscopy confirmed that the magnetic properties of the extracted sample originated from the high percentage of iron oxide. The hysteresis curve showed high saturation magnetization about 24.7 (emu/g), remanent magnetization of about 6.1 (emu/g) and a low coercive field of about 20 (Oe). The X-ray diffraction patterns identified a magnesioferrite (MgFe2O4) mineral structure. This result showed the novelty of iron sand from Sarmi, Papua when compared with that from Java Island.