Widespread nearly or nanoscale natural amorphous particles in critical zones from ore deposits

The advancement of nanotechnology has drawn more attention on synthetic nanoscale particles, while naturally nanoscale particles are often overlooked, especially nearly or nanoscale natural amorphous particles (nearly or NNAPs). Here, we report nearly or NNAPs obtained from multiple media. The sample media, including groundwater, ascending gas, soil and plant tissue, were obtained from eight concealed deposits with different types of minerals and three blank control group areas in the critical zones in China. The morphology, elemental combination and structure of nearly or NNAPs in these samples were characterized via transmission electron microscopy (TEM). The results show that the nearly or NNAPs are widespread compounds. This study established the elemental combination relationship of nearly or NNAPs and defined the particles as a native metal, S-O-, P-O-, and Cl-(O)-bearing as well as oxide nearly or NNAPs. Nearly or NNAPs could carry high proportion of ore - related elements, such as W, Pb, and Co in oxide nearly or NNAPs; Cu in S-O-bearing nearly or NNAPs; and Zn in P-O-bearing nearly or NNAPs. Nearly or NNAPs that carry ore-related elements were obtained from the surface area of the concealed deposits but not in the blank control group areas. With strong geochemical features, nearly or NNAPs can carry ore-related elements from the concealed ore bodies to the surface. These phenomena indicate nearly or NNAPs can be prospecting concealed ore bodies while possessing the environmental risks with high proportion of metal elements.