How_It_Works_Issue_99_2017

DID YOU KNOW? The Romans used lead in water pipes, food containers and even make-up, unaware that it was poisonous
Mining in Roman Britain
The invasion of Britain provided the Roman Empire with new sources of valuable ore
Claudius’ invasion of Britain began in 43
CE, and as his army conquered more
land, the Romans gained access to the
region’s rich mineral seams. Mining was an
important industry for the Romans, who used
the ores to make tools, jewellery and weapons.
During their rule, iron, copper, tin, lead, silver
and gold mines were constructed across Britain.
The Romans used several diferent mining
techniques, and pioneered hydraulic methods.
Hushing was used to extract ore near the
surface, and involved redirecting a river to
unleash a torrent of water that removed topsoil
to reveal the metals. In other areas, strip-mining
was used to extract shallow minerals by
removing the overlying ground.
Subterranean mining was a much larger
operation and was only used to unearth the
most valuable ores: silver and gold. Narrow
vertical shafts were used to penetrate into the
rock until ore was found, and these would then
widen into horizontal tunnels called galleries as
mining took place. Without explosives, ires
were likely set in the tunnels to expand and
crack the rock. The weakened rock could then be
drenched in water, which caused it to contract
rapidly and disintegrate. The workers, who were
usually soldiers, slaves or local people, used
stone and iron tools in the form of hammers,
picks, bars and wedges to extract the metals.
Britain became a huge mining centre within the
empire, and the scale and sophistication of the
work was not equalled until the Middle Ages.
Iron
33 iron mines existed in
Roman Britain, with the
majority in The Weald area of
Southeast England.
Mine locations
The Romans extracted a
variety of ores from sources
across England and Wales
Tin
With its operations centred in
Cornwall and Devon, tin was
mined to make coins and be
mixed with other metals to
make alloys.
Gold
Roman Britain only had one
area dedicated to mining gold,
which was in Wales at
Dolaucothi. The gold was
locked inside seams in
quartzite rocks.
Copper
The Romans already had
copper mining operations in
Spain and Cyprus, but it was
still excavated to mix with tin
to make bronze.
Silver
Silver was only found
alongside lead in Britain, and
the two minerals were
separated by being heated in a
process called cupellation.
12 per cent of miners under Roman rule died
each year from falling rocks and lung diseases
British gold mines
The Dolaucothi gold mines were constructed in
Roman-controlled Wales in 70 CE. The rich seam
was mined both on the surface and underground,
with shafts dug almost 50 metres into the ground
using just hammers and picks. Water was brought to
the site from local rivers via aqueducts to power
machinery and help wash away soil to reveal the ore.
A fort was built at nearby Pumsaint to protect the
mine and its valuable commodity from Celtic revolts.
Roman coins found in the area indicate that
mining activity continued until around the 4th
century, after which the mine was largely abandoned
until it was reopened during the Victorian era. Today,
the site is owned by the National Trust, with parts of
the mines open to the public.
Lead
Perhaps the most important
Roman commodity, Britain
overtook its closest rival Spain
as the main lead producer in
70 CE, causing miners in Spain
to complain.
Other minerals
Coal, marble and stone were
also mined. Coal was used to
heat baths and hypocausts;
very important for the
Mediterranean invaders not
used to wet and windy Britain!
It is estimated that one ton of gold was extracted
from the Dolaucothi mines before they were
closed in 1938
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