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Ore deposits are loci on Earth where energy and mass flux are greatly enhanced and focussed, acting as magnifying lenses into metal transport, fractionation and concentration mechanisms through the lithosphere. Here we show that the metallogenic architecture of the lithosphere is illuminated by the geochemical signatures of metasomatised mantle rocks and post-subduction magmatic-hydrothermal mineral systems. Our data reveal that anomalously gold and tellurium rich magmatic sulfides in mantle-derived magmas emplaced in the lower crust share a common metallogenic signature with upper crustal porphyry-epithermal ore systems. We propose that a trans-lithospheric continuum exists whereby post-subduction magmas transporting metal-rich sulfide cargoes play a fundamental role in fluxing metals into the crust from metasomatised lithospheric mantle. Therefore, ore deposits are not merely associated with isolated zones where serendipitous happenstance has produced mineralisation. Rather, they are depositional points along the mantle-to-upper crust pathway of magmas and hydrothermal fluids, synthesising the concentrated metallogenic budget available.

publisher: Elsevier articletitle: The application of deep eutectic solvent ionic liquids for environmentally-friendly dissolution and recovery of precious metals journaltitle: Minerals Engineering articlelink: http://dx.doi.org/10.1016/j.mineng.2015.09.026 content_type: article copyright: Copyright © 2015 The Authors. Published by Elsevier Ltd

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9The strength of rocks in the subsurface is critically important across the geosciences, with 10 implications for fluid flow, mineralization, seismicity, and the deep biosphere. Most studies 11of porous rock strength consider the scalar quantity of porosity, in which strength shows a 12 broadly inverse relationship with total porosity, but pore shape is not explicitly defined. Here

The largest and most significant type of geological deposit of platinum group elements (PGEs) is that associated with magmatic base metal sulfide minerals in layered mafic or ultramafic igneous intrusions. The common association of PGEs with sulfide minerals is a result of processes of magmatic and sulfide liquid segregation and fractionation. The mineralogical nature of the ores is dependent on a number of factors during sulfide liquid fractionation. The most significant of these with regard to the mineralogy of the two most important metals, platinum and palladium, is the presence and concentration of semimetals such as bismuth and tellurium within the mineralising sulfide liquid. Whereas rhodium, iridium, osmium and ruthenium are almost always present in solid solution within the resultant base metal sulfide minerals; should sufficient semimetals be present, Pd and especially Pt will form discrete minerals (such as platinum bismuthides) around the margins of, and possibly away from, the sulfides.

Magmatic systems play a crucial role in enriching the crust with volatiles and elements that reside primarily within the Earth's mantle, including economically important metals like nickel, copper and platinum-group elements. However, transport of these metals within silicate magmas primarily occurs within dense sulfide liquids, which tend to coalesce, settle and not be efficiently transported in ascending magmas. Here we show textural observations, backed up with carbon and oxygen isotope data, which indicate an intimate association between mantle-derived carbonates and sulfides in some mafic-ultramafic magmatic systems emplaced at the base of the continental crust. We propose that carbon, as a buoyant supercritical CO 2 fluid, might be a covert agent aiding and promoting the physical transport of sulfides across the mantle-crust transition. This may be a common but cryptic mechanism that facilitates cycling of volatiles and metals from the mantle to the lower-to-mid continental crust, which leaves little footprint behind by the time magmas reach the Earth's surface.

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