This can be subdivided into two main processes crushing and washing and this took place on a dressing floor. Much of the equipment on dressing floor was made of wood and so has disappeared from sites but there can be surviving clues to the organisation and operation of these sites.
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Bouse Teams, Beevors Shaft, Yarnbury Mine, Grassington, Wharfedale. |
Miners often worked as small teams
of sub contractors known as Partnerships. Each Partnership
contracted to work for a different rate depending on whether they were
working in a rich or a poor part of the mine. In a poor part of the
mine they would get a higher price for the amount of lead they produced
and in a richer part a lower price. This system aimed to even out the
miners wages. When the ore came out of the mine it was placed
in Bouse Teams, which are stone storage bunkers. Each of these
Bouse Teams kept the ore from each partnership separate. These
can be identified on many mine sites.
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Bouse Teams, Beevors Shaft, Yarnbury Mine, Grassington, Wharfedale. |
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Bouse Teams, Victoria Level, Old Gang Mine, Swaledale. |
Bouse Teams, Old Gang dressing floor, Sir Francis Level, Swaledale. |
Crushing - the bouse was crushed to separate the lead ore from any waste rock.
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The simplest the oldest form of crushing is the knocking stone. This is a large, stone anvil, usually surrounded by a pile of small spoil, which was used in conjunction with a flat hammer, called a bucker, to break the ore into small pieces.
The most common method of mechanised crushing in the 19th century was a roller crusher driven by a waterwheel. These can be recognised where there is a waterwheel pit, usually near to the bouse teams, surrounded by finely crushed spoil. There may also be a stone, counterbalance weight lying close by. Otherwise it may be difficult to distinguish from a waterwheel used for some other purpose. |
Hand dresing of ore using a bucker and knockstone, based on a 19th century illustration. |
Water powered ore crusher from Providence Mine Kettlewell, Wharfedale. Now at the Museum of Yorkshire Dales Lead Mining, Earby. |
Site of a water powered ore crusher, Hebden Gill, Wharfedale. |
Site of a water powered ore crusher, Gunnerside Gill Swaledale. |
Washing - Crushed ore was washed in a number of different devices to separate the heavy lead ore from the lighter waste. Lead ore has a high relative density and a number of different devices were used to separate it from the waste, which had a lower relative density. In other words, a piece of ore was much heavier than a similar sized one of waste. Many of the devices used were built of wood and have, therefore, left very little trace.
Two which can often be identified with some certainty are Running and Circular Buddles, both of which relied on a stream of water to separate ore from waste. The Circular Buddle is a later, mechanised development and was much more efficient.
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Dressing floor and Smelt Mills,Old Gang Mine, Swaledale. |
Running Buddle Crushed ore is raked back and forward in a flowing stream of water. The second smaller buddle or trunk box catches any small pieces of ore which escape the first trough.
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Hotching Tub This is a wooden box with a metal sieve inside that can be plunged up and down in the water to separate the heavy ore from waste rock. |
Circular Buddle |
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Compare these images to the reconstructed dressing floor at
The North of England Lead Mining Museum at Killhope in the North Pennines