Silver mining and the English Crown:

direct working of the Devon mines, 1292 to 1350

Presentation made to the IVth International Mining History Congress

held at the Faculty of Mines, University of Guanajuato, Mexico, hosted by the University of Guanajuato and the Instituto Nacional de Antropologia e Historia (INLA)

10 to 13 November 1998


What marks out silver mining in England and Wales is the organisational change which took place in the 13th and 14th centuries.

The industry effected a transition from small scale operations, in the hands of independent miners, to relatively large scale capital intensive mining organised on a proto-entrepreneurial basis.

On the other hand, lead, and to a lesser extent iron, were to remain locked in their medieval form well into the 17th century.

The catalyst for change in the silver industry was the exercise of Crown prerogative and the direct working of the Devon mines in the period 1292 to circa 1350.

Silver mining prior to the 13th century.

Principal sources of silver were lead ores - galena (lead sulphide) and cerussite (lead carbonate) - or tetrahedrites associated with copper mineralisation.


Found in the Carboniferous rocks of upland Britain - Mendip, north-east Wales, the northern Pennines, and to a lesser extent the Derbyshire Peak District and south-east Wales, with largest output coming from Tynedale in the northern Pennines.

Mineral rights, including silver bearing ores, linked to lordship of the land. In the case of the major producer, Tynedale (the 'mine of Carlisle'), these were in Crown hands but in some areas - notably County Durham and the Manor of Wells, on Mendip - the right to mine silver was granted to ecclesiastical lordships.

Organisation of mining was generally governed by custom - giving control of the means of production to the miners and control of the produce to the mineral lord through pre-emption.

Silver production, primarily from Tynedale, peaked in the 1160s - evidence for an earlier peak is masked by the Scottish occupation of Cumberland, 1135-54 - but had fallen to negligible levels by the end of the century.

The Crown's right of prerogative over silver-bearing ores.

First invoked in the 1260s in respect of a potential source of silver in north Devon - found outside Crown lordship.

A landowner's right to ores of base metals, free from silver, were confirmed.

Thereafter the rights to silver-bearing ores were vested in the Crown, with the continued exception of Durham and Wells, until removed under the Mines Royal Acts of 1689 and 1693.

However, the Crown chose not to press its claim in those mining fields, governed by custom, which were outside Crown lordship.

The only legal challenge to the status of silver-bearing ores - the Case of Mines in 1567 - decided in favour of the Crown.

Direct working of the Devon mines.

Mines at Bere Ferrers and Combe Martin, working lead based silver deposits in the older 'Devonian' rocks, opened up in 1292 under direct Crown control.

'Keeper' appointed, reporting to the Exchequer, with his activity monitored by a controller but allowed the flexibility to improve operations.

Large workforce assembled - drawing on the established lead mining fields for skilled labour - many of whom were pressed into service.

Workings were initially shallow but adit drainage was required by 1297-8.

Ores originally smelted using only simple wind-blown bole hearths but that method was found wanting - only capable of reducing the larger 'bing' ore and leaving appreciable amounts of lead and silver in the residues.

There ensued a period of experimentation with smelting methods - including the 'hutt', a form of liquation - culminating in the bole / furnace complex which served the lead-silver industry until the advent of the ore hearth process in the 16th century.

Finance for development work came from the Exchequer. Money was either diverted from locally collected taxation or provided as cash from the London mint. On occasion funds were generated by local sales of sterile lead.

The Comb Martin mines were abandoned in 1296 but those at Beer Ferrers continued in production until the Black Death. Output peaked at 23228 ozs in 1297 and again at 21516 ozs in 1306.

With prospect of good returns in 1299 the mines were granted to Italian bankers, the Friscobaldi, as security for a loan but, in their short tenure, they paid little regard to maintenance or development work and left the mines in a poor state.

The mines were back under direct working in 1300 but it was four years before repairs were effected and there was renewed production. There then followed a period of further investment in capital works to improve free drainage and reduce the reliance on labour to haul water from the workings.


In the 1320s the working's were rich but again troubled by water, enough to justify the driving of deeper drainage crosscut adits.

When the Black Death hit the South-West of England in 1348/9 the mines were reduced to the reworking of slag residues and underground working was abandoned.

The move to fixed term leasing.

Silver mining resumed, at Combe Martin, in the 1360s but direct working was discontinued and the mines were held on lease from the Crown.

Over next few decades the form of the Crown lease was developed to include all those elements found in modern leases - royalty, dead-rent, fixed terminal date - and the right of pre-emption.

The mines were usually granted on a county basis. The scale of which and the deep seated nature of the deposits in the South-West of England, and later in Wales, meant that only those entrepreneurs with sufficient capital could hope to succeed.

The factors behind direct working.

To understand the reasoning behind the move to direct working we must examine the factors - economic, technological and administrative - which might have influenced the Crown's decision making.

The move to direct working came at a time of increased pressure on royal finances, due largely to Edward I's martial policies.

Profits from silver mining had the attraction of being outside the control of Parliament.

It has been assumed that central control was required to muster the resources for deep mining but direct working predates the evidence for deep mining.

The miners from the lead mining field brought no particular deep mining skills and the tinners employed in adit drainage work were utilising their skills in draining shallow, but wet, stream workings.

Similarly, with smelting simple techniques were first used and only when they failed new ones developed through experimentation.

Only in mustering such a large work force was the central control provided by direct working effective - the precedent having been set in the castle building programme in Wales.

Parallels with central Europe in the exercise of regalian rights over silver cannot be extended to the organisation of mining. The frontier environment of the European expansion eastwards in the 13th / 14th century justified the self regulation as it had in the northern Pennines in the 12th century. The Devon mines were in lowland agricultural communities with the benefit of good communications, allowing regular contact between officers and the Exchequer.

Good methods of accounting had become standard by the late 13th cetury, allowing for regular monitoring of production and expenditure.

It could be argued that the 'private sector' - the independent miner working and governed by custom - was too inflexible to expand into new areas of production. Restricted by customary boundaries would be unwilling to open up new deposits without the benefits custom gave them.

The Crown could have enabled the transfer of custom to new areas but, without efficient local administration, that placed the potential for profit in the hands of the miners. It was no doubt remembered that ineffective administration in Carlisle in the latter half of the 12th century had resulted in the loss to the Crown of approximately one third of its income from the Tynedale mines (the mine of Carlisle) through an accumulation of debts.


The Crown's actions in taking on the direct working of the Devon mines appears to have been prompted by the desire to maximise its income from silver mining.

Using an administrative system, already tested in the castle building programme, it ensured continued control of resources whilst allowing the flexibility required to improve production.

Although there is no evidence that the Crown opened up the Devon mines with deep working in mind, by its willingness to provide the capital necessary to develop the mines, it set the pattern for the application of capital intensive techniques in the industry.

By late 14th century the technological problems of deep working were exacerbated by the rapid demographic decline during the plague years. Whilst the financial demands of royal government remained as high as those a century earlier, the administrative problems of marshalling the resources, material and human, required for deep mining influenced the move to a policy of leasing the mines to private individuals.

In choosing to farm out the mines in a form accessible only to men of substance the Crown ensured control over its income from silver. It also laid the foundation for an entrepreneurial system which was to dominate non-ferrous metal mining into the modern period.

The full text of the paper will appear in the published papers of the Congress.

Details from the Organising Committee, Direccion de Estudios Historicos, INAH, Anexo al Castillo de Chapultepec, Apartado Postal 5-119, Mexico, D.F., C.P. 06500 e-mail miningcongress@infosel.net.mx


Peter Claughton / Dept. of History
Last modified 10 December 2000