LAUSR

The New Caledonian archipelago, located approximately 2,000 km east of Australia, is home to one of the world’s largest ophiolite complexes – uncommon rock units approximating those found in the Earth’s mantle. New Caledonia has the 3 largest nickel reserve in the world and ranks 5 in global production [1]; nickel is mined from enriched clay minerals formed during tropical weathering the ophiolite underwent since emplacement 35 million years ago [2]. New Caledonia is also home to the world’s 2 most extensive coral reef system. The lagoon between the land and reef crest has been designated a UNESCO World Heritage Site. The present work explores silver nanoparticles discovered during a high-resolution transmission electron microscopy (HR-TEM) based assessment of previously characterized (by other techniques) Ni-rich clay minerals associated with mine waste. These nanoparticles are potentially linked to toxic silver bioaccumulation observed in lagoon organisms [3][4]. This investigation demonstrates the novel data HR-TEM can reveal in geological environmental assessments.