Derbyshire Dome

This limestone outcrop is surrounded on the west, north and east by a horseshoe-shaped formation of younger sandstones (gritstones) and shales, known as the Dark Peak.

About 30 million years later, coarser debris from rock erosion was washed onto the earlier shell layers.

Later erosion of the younger Namurian-age sandstones (the finer shales and the rougher gritstones) has exposed the limestone strata.

At times when parts of the sea bed rose, plants grew and their decayed remains formed a few shallow deposits of coal on the western side of the dome.

Volcanoes around the sea bed spewed out lava flows which have formed local outcrops of volcanic basalt (dolerite).

[2][3] The Peak District is rich in minerals, formed from geothermal fluids being forced up through the fissures in the limestone.

When these cooled and crystallised they formed widespread hydrothermal mineral veins of galena ore (lead sulphide), fluorospar, barytes, calcite and copper.

This has created typical fluviokarst features of dry valleys, steep-sided gorges, and cave systems with stalactites and stalagmites.

[10] Ice Age animal bones were found by quarrymen in 1901 in an underground chamber at Victory Quarry at Dove Holes.

[1][2] The limestone crags, cliffs and quarries and the gritstone edges of the Peak District offer some of the most challenging rock climbing in Europe, with over 10,000 graded routes.

Lime is produced easily by heating limestone and it has been used in mortar since ancient times, for fixing together the stone blocks of buildings.

Numerous lead pigs (ingots weighing about 50kg) bearing the mark for Lutudarum have been discovered in Derbyshire, near Hull and in Sussex.

Modern uses are for glass manufacture and production of hydrogen fluoride (with wide-ranging applications from pharmaceuticals to refrigerants).