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SUMMARY:Roman Mining Technology in Britain - Dr Peter Lewis\, Reader in Fo
 rensic Engineering\, Open University
DTSTART:20110126T193000Z
DTEND:20110126T210000Z
UID:TALK29264@talks.cam.ac.uk
CONTACT:Dr Geoff Hale
DESCRIPTION:The Romans introduced advanced mining methods to Britain follo
 wing their invasion in 43 AD\, especially hydraulic mining using large vol
 umes of water. They used the water in several ways: for prospection by rem
 oving overburden to expose bedrock\, for development of veins \,  washing 
 ore-containing material and powering machines for crushing hard rock ores.
  The methods are shown best at the gold mine of Dolaucothi following their
  invasion of South Wales in ca 74 AD and nearby sites in the Tywi valley. 
 It followed the large scale mining developments in Spain (25 BC onwards).\
 n\nThe hydraulic remains at Dolaucothi are substantial and show how the mi
 ne developed from prospection of surface deposits\, discovery of veins\, o
 pencast working and finally underground exploitation. A small stream of wa
 ter was used to wash both overburden and crushed rock using gravity separa
 tion to extract the gold. The largest reservoir was used in this way\, and
  a later tank (Melin-y-milwyr) built close to the main opencast. Each syst
 em used a stepped series of tanks with washing tables between so as to max
 imise gold collection using riffle technology. Mercury amalgamation may ha
 ve also been used to remove the last traces of gold dust. Surface gold cam
 e from the oxidised zone\, where pyrites are converted to iron oxides\, of
 ten liberating fine gold within the crystals. \n\nTowards the end of the c
 entury\, they penetrated vein deposits\, and is attested by the discovery 
 in the 1930s of a drainage wheel fragment in a deep stope. It was part of 
 a sequence of such wheels\, well known from southern Spain at Rio Tinto an
 d elsewhere (Portugal and Dacia). Gold separation became more difficult an
 d needed crushing machinery\, especially a four-stamp mill worked by an ov
 ershot waterwheel. The fragments would then be ground to fine flour before
  final washing. Some gold may have been lost since it was locked inside py
 rites. Both surface and underground mining needed skilled\, honest and rel
 iable labour\, probably soldiers rather than slaves.\n\nOther potential Ro
 man mines occur in Mid and North Wales\, Shropshire\, the north Pennines a
 nd Scotland. They deserve intensive field work to examine reports of hydra
 ulic remains. \n\nParallels with modern evidence of hydraulic mining inclu
 de the known history of the California gold rush of 1848/9 and the Yukon r
 ush of 1896/7\, as well as evidence from Uganda from the 1930s\, and Mongo
 lia in recent times as the result of the financial crisis of 2008 onwards.
 \n
LOCATION:Department of Materials Science and Metallurgy\, New Museums Site
 \, Pembroke Street\, Cambridge CB2 3QZ
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