MagResource: Environmentally conscious, geophysics-based resource definition.

Magnetite has characteristic density and magnetic properties which contrast strongly with most common minerals and rock types. Provided magnetite grains within a resource have relatively uniform grainsize and composition and sit within a background of uniform density, linear relationships exist between magnetite and iron content, density, and (except at high concentrations) magnetic susceptibility. In the MagResource method these relationships are integrated with geophysical modelling to infer Iron content in magnetite resources.

The great advantage of the MagResource method is that we use physics to invert a magnetic field that is scalar to the resource. Whilst high resolution magnetic data is requisite, spatially representative sampling is not, because our geophysical inversion is already spatially representative. Samples which span the range of susceptibilities and magnetite contents are used to define the gradient of magnetic susceptibility: Iron content, which converts a modelled magnetic moment into contained iron. By this quantification of iron resources using 99% non-invasive technology, we drastically reduce early exploration expenditure and define resources faster with fewer cultural and environmental impacts.