Florence Mine

Also within

Cumbria County

Condition (Natural England)

Geology & landscape

Geological Period: Triassic · Rock Type: Granite

Landscape processes: Karst, Volcanic / Igneous

Description

Description The Florence or Beckermet Mine provides excellent three dimensional exposures through the largest 'flat' type iron ore replacement body in the West Cumbria iron orefield. These epigenetic ore deposits are within the Visean limestones which surround the Lake District area and are related spatially to Variscan faulting. The ores, of Permo Triassic age, are believed to have formed by replacement of the limestones by the precipitation of iron oxides from iron bearing oxidising brines. The origin of these brines is a subject of much scientific debate, but seems to be complex multiple source, with upward rising thermal brines derived from basinal sources to the west, mixing with iron bearing groundwaters. The source of the iron is also uncertain, with contemporaneous red bed desert sediments and the Eskdale Granite both postulated. At Florence Mine, the variety and form of the ore is superbly displayed in situ. The main types of ore, massive, kidney, specular and soft are all visible and spatial relations with faulting and lithology can be studied uniquely. The presence of fluorite, as well as barite, in the ore is also unusual and provides support to the ore genesis models. Florence Mine is a key site for research into iron ore mineralisation in Britain. It provides the most outstanding example available of a type of mineralisation which is different from the normal 'Bilbao type' iron ore replacement deposits and which is almost unique to Britain.