Susanta Paikaray is presently working on various aspects of aquatic geochemistry along alluvial plains. He currently works as an Assistant Professor at Panjab University Chandigarh (India) in the field of Environmental Geology, Climatology, and Aqueous Geochemistry. He obtained his PhD degree on environmental and sedimentary geochemistry from IIT Bombay (India) and MSc in Applied Geology from IIT Roorkee (India). His research interests include mine drainage, wastewater treatment, mineral and sediment geochemistry, hydrochemistry and investigating soil, groundwater and crop pollution by metallic and non-metallic contaminants, microplastics in aquatic environment, mine tailing, and urban waste management. He has been working on schwertmannite for several years, especially aspects of stability, chemistry, and environmental applications. Stefan Peiffer is working on the geochemistry of aquatic systems for more than 30 years with a focus on coupled geochemical and microbial processes in sedimentary and groundwater environments. With a special emphasis on the interaction between the iron and sulphur cycle, his present research includes the kinetics and mechanisms of surface-mediated mineral transformations. He has also studied the effect of advective groundwater flow on biogeochemical process rates during groundwater–surface water interactions, with attention to acid mine drainage affected systems including schwertmannite as a key mineral.