The Earth Story

Mineral tree Mineral bearing fluids often pass through rocks, sometimes leaving behind a little parting gift on their way. This happens when the fluids encounter different conditions, including both physical ones such as pressure/temperature and chemical conditions such as acidity or the oxidising/reducing potential of the rocks themselves. The fluids often leach elements out of the rocks, leaving others behind in a complex series of chemical reactions usually placed under the umbrella term hydrothermal alteration, that covers a huge range of transformations dependent on the nature of the interacting rocks and fluids. In this case, dendritic veins of the manganese mineral pyrolusite have been precipitated along networks of microcracks as the fluids pass through, leaving behind these beautiful arborescent mineral formations. Loz Image credit: Aram Dulyan