During the late medieval period the mining of silver-bearing ores effected a transition from a handicraft form, based on the activity of independent miners, governed by custom and with the minimum of royal involvement, to a capital intensive industry subject to central management in which the miner was an employee of the Crown or its lessees. After 1500 new centres of silver mining were opened up in mid wales and in the south-west of England, where earlier (medieval) sites like Combe Martin were reopened and proved particularly productive.

At their conquest of England in 1066, and the subsequent occupation of parts of Wales, the Normans inherited a dispersed, small scale silver mining industry exploiting silver bearing lead ores. The mines were to be found on the Carboniferous limestone uplands like the Derbyshire Peak, Mendip, the Welsh borders and the northern Pennines where shallow enriched ore deposits had escaped the effects of glaciation. Deeper seated deposits in the pre-Carboniferous rocks, particularly in the South-West of England which escaped the full effect of glaciation, were not exploited until the latter part of the 13th century and it was the mines of Tynedale and upper Weardale in the northern Pennines which provided the peak of English silver production in the mid 12th century.

Prior to the thirteenth century the ownership of silver bearing ores resided with the lord of the soil. The English Crown sought no greater control over production than its right of lordship over the principal sources, in the liberty of Tynedale, allowed and was willing to relinquish control of resources in a grant of lordship, as was the case with the bishop of Durham's lordship over the upper Weardale mines. It was only in mid 13th century that regal authority was extended to a prerogative on silver-bearing ores although the Crown respected existing rights, culminating in the direct working of the Devon mines in 1292.

Working of the Tynedale mines - the Mine of Carlisle - of the 12th century was in the hands of the miners themselves. Governed by custom the miners were largely self regulated, paying a portion of their produce - one ninth after tithe - to the Crown as lord. The income generated being leased to local collectors who accounted for the farm to the sheriff in Carlisle who record it along with other farms for the county of Cumberland. Thus the Crown took no direct part in the production of silver, relying on its right of pre-emption to direct silver to the mint. When, in the late 13th century, the Crown took control of new centres of production in Devon it chose to operate them using a directly employed work force - some of which it impressed in the customary lead fields of Mendip, north-east Wales and the Derbyshire Peak, later supplementing them with tinners from the Stannaries - supervised by Crown officers. The Devon mines - centred on those at Bere Ferrers - were worked in that manner for a little over fifty years.

By late 14th century the problems of increasingly deeper working of the silver deposits in Devon were exacerbated by the rapid demographic decline during the plague years. Mining ceased in about 1350 and when reopened in 1360 the Crown chose to lease them on a county basis, withdrawing totally from direct working. Mines were generally worked by or on behalf of the lessee and only occasionally, as at Bere Ferrers in the 1450s, were discrete sections of the workings sublet to individuals or small partnerships.