August 2015

Metalloproteins play essential roles in biology and medicine. Calcium is a major component of bones, while electron and oxygen transport in the body relies on iron and copper. Isotope fractionation of metal stable elements uniquely reflects specific biochemical pathways. Variations in these isotope ratios from normal levels in body fluids can be used as reliable markers of pathological conditions. Metal stable isotope fractionation reflects the energetics of bonding, is amenable to theoretical calculations and is fast becoming a powerful medical diagnostic tool. Examples include how calcium isotopes can be used to monitor bone loss, how iron isotopes can react to genetic disorders, and how copper isotopes can help track cancer progression.

Stable isotopes are valuable biogeochemical markers for solving problems faced by society today, such as distinguishing authentic from adulterated foods and beverages or tracing the origins of illicit drugs. Hydrogen and oxygen isotopes in water exhibit distinct continental patterns (isoscapes), which provide useful region-of-origin information. We ourselves reflect the stable isotope ratios of the water we drink and the food we eat: our hair records any isotopic changes to our diets, which can often be related to location. This latter aspect can be of interest to law enforcement in determining the origins and travel histories of unidentified murder victims.

Geochemical data and models can provide a baseline by which to compare changes in the composition of surface waters, groundwater, the atmosphere, soils, and sediments in the coastal megacity of London. The usefulness of geochemical data is dependent on effective communication, which can be challenging. Geochemical tools and approaches can provide evidence to underpin decision making as well as solutions to environmental problems in cities. Geochemists must move beyond simple provision of evidence to describing a solution and then convincing politicians to put this solution into practice.

The close links between mineralogy and materials science are leading to major developments in how society deals more effectively with energy and environmental challenges. The fast expanding field of “environmental mineralogy” helps mitigate major environmental issues related to the impact of anthropic activities on the global ecosystem. Focusing on energy related materials and environmental cleanup, this article shows how minerals inspire us to design new materials for advanced technologies needed for energy production, managing contaminated areas, and disposing of nuclear waste. We illustrate the environmental importance of nanomaterials, non and poorly crystalline phases, and the interactions between minerals and ubiquitous microbial activity.

The prosperity of our societies and our standards of living are directly related to our ability to find, exploit, and manage our metal and mineral resources. Metal and mineral deposits are, in fact, geochemical anomalies and, as such, applied geochemistry plays a critical role throughout the mineral resources value chain, from early stage exploration to mine closure. The fundamentals of element mobility (i.e. transport and fixation) in the near-surface environment are used by geochemists to detect mineral deposits at depth, reveal element distributions in and around deposits, assess the total geochemical environment, and refine effective and benign extraction and waste disposal techniques. Both pure- and applied-research ventures play fundamental roles in providing the techniques to manage metal resources and thereby benefit society.

As geochemists and mineralogists, we are well aware of the impact of our science. We can often reel off examples of how our discoveries have influenced industry and improved humankind’s knowledge about how the Earth works, as well as how natural and anthropogenic processes have led to its present state. Moreover, because of a century of analytical developments and conceptual breakthroughs, geochemists are now versatile and can now work across the entire spectrum of the Earth sciences. However, we are not so good at promoting the social and economic impacts of geochemistry.