David Mustart Talk for the Tucson Gem & Fine Mineral Show 2025

Dr. David Mustart, Professor Emeritus of Geology at San Francisco State University, will present a talk titled “Unraveling the Conditions of Crystallization of Native Gold.” This engaging talk will delve into the fascinating processes that shape one of Earth’s most coveted elements.

Among the 5,800+ known minerals, only 26 are classified as native metals. These unique minerals crystallize using atoms of a single element, setting them apart from all other mineral classes. Because of this simple distinction, their habit gives a direct signal of conditions of crystallization including temperature, pressure, chemical environment and time.

Native Gold, in particular, exhibits a remarkable diversity of crystal forms, such as dendrites, hoppers, herringbones, leaves, ribbons, twins, euhedral crystals, and wires. The origin stories of these forms are deeply intertwined with geological phenomena like plate tectonics, deposit types, and rare, singular events such as earthquakes and mineral reactions.

Among these forms, true gold wires – distinct from pseudowires – represent the rarest and most enigmatic habit of crystallized gold. Their formation poses a unique challenge to scientific understanding and will serve as a major focus of this intriguing presentation.

Host or Publisher The Tucson Fine Mineral Gallery