holme bank mine

Holme Bank mine is located in Derbyshire in the 300-million-year-old carboniferous limestone beds to be found around Bakewell, more specifically in the highest reaches of the Monsal Dale limestone formation. Along with the nearby Pretoria mine, Holme Bank was the last of two operational chert mines in Derbyshire, although initial operations date back to 1778 when it began list as a quarry.
Chert is a fine-grained, flinty siliceous rock usually found in veins in the uppermost beds of a limestone strata. It was worked into tools in prehistoric times, due to the ease with which it could be shaped by chipping off flakes to produce sharp edges in a similar manner to flint. Latterly, and more recently chert was the ground into calcined flint and used as a whitening agent in earthenware manufacture. Here at Holme Bank, 90% of the limestone has been replaced by a laminated form of chert. The chert in the mine is in two beds, up to 2.4m thick: the main mottled throstlebreast bed and above it the more flinty roof chert. These were overlayed by roof limestone and underlayed by holing bed limestone. The latter was removed to undercut the chert.
The popularity of chert grew and it becoming an in-demand stone in the mid-1700s was down to Thomas Benson who patented a new 'wet' process of grinding flint for the usage in the pottery making process. Previous grinding of flint had utilised grain-grinding millstones, but this produced copious dust, resulting in workers dying from silicosis. Benson's first attempt at a 'wet' process was in 1726 using iron balls. This had the unwanted consequence of leaving deposits of iron in the pottery, hence he then replaced this with the coloured granite stones and then chert which gave superior results still. The use of chert to grind flint was adopted wholesale by the renowned pottery maker Josiah Wedgwood at his Etruria works in Stoke-on-Trent. In 1772, Wedgwood cited Derbyshire chert as a successor to granite millstones due to it leaving black specks in the pure white flint. This led to increased extraction of chert from Holme Bank and at other locations in the Bakewell area for use as 'runners' and 'pavors' of the circular flint mills.
Initially, chert was quarried but this destroyed land and when these supplies ran out in the mid 1800 chert extraction shifted to mining. Mining was made viable by the rising price of chert and declining transport costs. Access to the mine was from adits in a quarry at Bank Top and the steep workings extended beneath the road to connect with the earlier Greenfield shaft. The chert bed lies on a 1-in-3.7 gradient and the mine was subject to flooding in severe winters. Illumination was by mains electricity in addition to carbide lamps carried by the miners. The chert bed was on average 9 ft (2.7 m) thick, though up to 18 ft (5.5 m) in places. Due to the hardness of chert, it could not be drilled so blasting to extract it was not practical. Hence extraction was done using the 'undercut method. Three foot of limestone was removed from under the chert using explosives. The chert was then supported on pillars made of small limestone stones (or sprags). When a suitable vertical joint was reached the pillars were blown out causing the chert block to fall, under its own weight, to the mine floor. The blocks could weigh up to 200 tons. They were then cut up in situ into up to 3 tons. A hoist powered by compressed air loaded the blocks onto flat wagons, drawn to the surface by compressed air winches, along a 1-foot 6-inches gauge railway. The ‘waste’ limestone was built up into substantial roof supports.
The introduction of compression Air drilling revolutionised extraction and was in use from about 1880 in Holme Bank.
While mining chert was not as high risk as some occupations, it was not without its dangers. In 1899, a year after the lease on the mine passed for a period of 11 years to Sir Shirley Harris Salt on, 19th June, 53-year-old Matthew Hollis of Bakewell was killed after returning to a charge that didn’t go off. While he and two other men were setting a second charge, the initial charge went off. A second fatality followed in 1919. On 17th April, the 62-year-old John Bond was killed, returning to fire his 11th charge of the shift, when it went off prematurely.
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[@jasonstuarthartley2310]

I'm looking forward to it

[@well-knownun-known2699]

Good exploring Urban. 👍

[@HeidiGill-vl6lc]

Great info👋🏼🙌🙌

[@Peardrop]

Afternoon everybody 😊

[@columbo7927]

Interesting mine explore folk Watchout for those glow stick folk roaming Cheers Will Thank you very much

[@theurbanlegenduk1760]

So glad you enjoyed it mate 💯 and for those glow stick folk roaming I'm not worried I can spot them a mile a way🤣😂💯💖👍

[@AbandonedLandscapes]

That looked cool mate 👍 very interesting

[@theurbanlegenduk1760]

It was!

[@kernow..exp.]

Great video mate

[@theurbanlegenduk1760]

Glad you enjoyed💯🙂👍

[@VikingExploration60]

HaHa thanks for the shout, but you got it slightly wrong its Viking Exploration 😂

[@theurbanlegenduk1760]

Sorry mate my dyslexic kicked in. I was relying on voice typing and the combination of both don't always work out. It was great to meet up with everyone and it was a great day cheers💯💖👍