set: minerals // series: // picture: 8
Mineral deposits come in a variety of shapes and sizes. In this example (from a prospect for gold and copper in Montana, western USA) the metallic minerals are present in numerous, small, cross-cutting veins in granodiorite host rock. The minerals were probably formed from hydrothermal fluids permeating the fractured igneous rock. If mining were to take place at this deposit it would probably necessitate complete removal of veins and host rock, and a consequent dilution of the metallic minerals with waste rock.
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