An accumulation of minerals along a fault or a joint. The minerals are usually igneous in origin. Related Articles: The Golden Dinosaur from the depths of the London Mine: Mystery of GenevieveUrban geology (Part 14): Two granitesTauern gold: The history of gold mining in the Central AlpsFabulous Fluorite: Derbyshire Blue JohnUrban geology (Part 1): The battery on the Sloterweg« Back to Glossary Index