We thought it would be interesting to set out some of the history of how the Romans mined for Welsh gold two thousand years ago.
One of the main reasons the Romans invaded Britain was to get their hands on its metals and minerals. Lead was highly sought after. It was used for water pipes and once liquefied it could be mixed with tin to make pewter. In addition, the silver also found in the ore could be extracted to make coins and tableware. By AD 70 Britain was the Empire’s biggest supplier of lead and silver. The writer Pliny the Elder in his Natural History describes the abundance in the new colony: ‘The lead we use in the manufacture of pipes and sheets is mined with considerable effort in Spain and the Gallic provinces; in Britain, however, it is found on the surface in such large quantities that there is a law limiting production.’ (This quota was imposed after the Spanish lodged a complaint with the Emperor). To obtain this level of productivity, even though the mines were open-cast demanded harsh work. Over 10% of the workforce died each year.
But there was a far worse mining job in Roman Britain: looking for the most precious metal of all – gold. It was worse because finding gold meant deep-cast mining. Going under ground was very risky. You might assume that this was a job for slaves, but there is evidence from elsewhere in Europe that freemen did the job too.
There was a Roman gold mine at Dolaucothi in Wales. Using their famed technology, the Romans channelled water for miles via a system of aqueducts to two great reservoirs on top of a nearby hill. This water was then released in a powerful flood to denude the hillside of greenery and soil and expose the quartz-rich rock in which the gold could be found. After this sudden and spectacular demonstration of the power of Roman engineering, the rest of the gold-mining process was simply a question of hard graft. It is estimated that the Romans removed half a million tons of rock from Dolaucothi in the 300 years the mine was operational. And it was all done by hand.
The slaves had only the most rudimentary tools to do this: simple hand-picks and baskets, and wooden carriers to transport the ore. The reason so much rock had to be shifted lies in the way gold-bearing quartz is laid down. A mineral like coal is comparatively simple to extract. It lies in seams, a geological stratum that can sometimes be diagonal to the surface, but always lies in an identifiable strand between the same strata of rock above and below. Quartz, though, is produced by ancient volcanic activity. It is the solidified result of molten ore shooting into irregular fissures in the rock. So it lies not in seams, but in veins that run higgledy-piggledy through a mountain. Sometimes they go up, sometimes down. They may widen into a great expanse of ore, or peter out into nothing. Following the veins is a frustrating game of trial and error.
The miners worked in a labyrinth of tunnels. The roofs of the shafts were propped up by wood but the natural movement of the earth could crack the props like matchwood. The conditions were cramped, dangerous and dark. Very dark. Although the miners had lamps fuelled by animal fat or olive oil, they were smoky and gave off little light. It is possible that the miners often hacked away in the pitch black, only able to tell the difference between the smooth shale and sharp quartz by touch.
In order to clear the rock around the seam, they banked faggots of wood against the rock face, set fire to them and then kept them burning for a couple of days in order to heat the rock to a high temperature. As it heated up and the smoke drifted along the tunnel, the conditions must have been intolerable for those charged with keeping the fires alight. In the choking smoke their dim lamps would have been virtually useless. But the most dangerous part was yet to come.
When the rock was so hot it began to glow, it was suddenly cooled by throwing water or vinegar on to it. The sudden contraction caused by this change in temperature created violent explosions. The miners, choking in the smoke of two days’ worth of fire, had to deal with collapsing rock face and flying debris in virtual darkness.
All this waste rock was then carted out down the long tunnels by hand and dumped before the miners could start chipping away at the newly exposed quartz with their picks.
But quarrying the veins was just the start. They had to be broken into smaller chunks until they were portable. Then they too were carried out into the open. Quartz is very hard and brittle, and the specks of gold in it are tiny. So the quartz was smashed as finely as possible and put on to woollen fleeces. The stone was then washed away, leaving the gold (which is heavier) on the bottom of the fleece. This was then burnt and amongst the ashes were tiny flecks of gold.
We don’t know how many miners died at Dolaucothi extracting gold to be turned into fine ornaments for wealthy citizens around the Empire. Anyone who has been to the Welsh mountains in winter will know how harsh the conditions can be. The fort at Dolaucothi was too small to accommodate the workforce so the slaves were housed, possibly shackled, in their own huts. Few of them would have shed a tear when at the beginning of the 5th century the mine was finally abandoned – to be left dormant until the Victorian era.
But if the gold mine at Dolaucothi was a symbol of harsh conditions it was also a symbol of the sophistication of Roman economics and culture. What followed when they left Britain was hardly an improvement.
(The above is an extract from Tony Robinson’s book, The Worst Jobs in History.)
These days there are no working gold mines in Wales. The Welsh gold Aur Cymru Limited uses to make your pure Welsh Gold wedding rings and Welsh Gold jewellery is found by the traditional method of gold panning.