Chert is similoar to flint, being a microcrystalline silica, but it is found in limestone bedrock rather than chalk. The mineral is most often used to give strength to bone china after grinding but can also be used as a roadstone. Near Bakewell it can be found in large beds. Holme Bank Mine continued working until 1968 although limestone ‘deads’ were later used to produce breeze blocks for construction.
Around two miles of passages remain and a number of artefacts - rails, drills tubs for example. Part of the mine has now flooded and is used by cave divers. Access can be arranged through the Derbyshire Caving Association for those with BCA Insurance.