Galena with Slickenside

A small cabinet size slab of Calcite, Fluorite and Galena veinstone with one side featuring a solid face of slightly undulating, naturally polished Galena, a splendid example of a slickenside.  Slickensides form by frictional movement along a fault plane where the two opposing surfaces have rubbed against one another, so generating this naturally polished surface.  The detailed accompanying label gives the most probable locality as Grassington in North Yorkshire, based upon similar specimens in once held in the Museum of Practical geology in South Kensington, London.