This Special Issue covers a broad range of topics related to the mineralogy of noble metals (Au, Ag, Pt, Pd, Rh, and Ru) and the occurrence, formation, and distribution of these elements in natural ore-forming systems. This collection of eleven research articles discusses various problems related to these topics. I hope this Special Issue will contribute to a better understanding of the genesis of gold, silver, and other noble metal deposits as well as the behavior of these elements in endogenic and supergene environments, and suggest ways forward to solving the problem of their full extraction from ores.

Natural nanomaterials and nanotechnologies are all around us, which inevitably leads to these questions: What are these natural nanomaterials made of? Where can we find them? What can they do? Answering these questions will facilitate new and environmentally friendly ways of creating and manipulating nanoscale materials for the next generation of new technologies. A truly multidisciplinary resource, this book brings together studies from astronomy, physics, chemistry, materials science, engineering, geology and geophysics, environmental science, agricultural science, entomology, molecular biology, and health and provides an invaluable resource for learning how various scientists approach similar problems.

Noble Metals and Biological Systems examines the relationship between noble metals (gold, silver, and platinum group metals) and biological systems. The book is divided into three parts. Part 1 is concerned with the analytical chemistry of noble metals and includes a description of the latest methods of analysis. Part 2 describes such topics as ecology and environmental science of noble metals as they pertain to biogeochemical exploration, noble metals in hair, the environmental geochemistry of palladium, microorganisms and noble metals, animals and noble metals, and a general survey of noble metals in the environment. Coverage is comprehensive and includes information regarding the use of dogs and termites as field assistants in mineral prospecting, as well as the fascinating story of the "gold bug", a microorganism that plates itself with gold. Part 3 is devoted entirely to noble metals in the treatment of disease and includes chapters describing the use of osmium and gold for arthritis treatment, silver as a bactericide, and platinum and ruthenium as anticancer agents. Noble Metals and Biological Systems will provide fascinating reading for applied geochemists, environmentalists, public health specialists, ecologists, microbiologists, clinical biochemists, oncologists, and specialists in rheumatic diseases.