Approximate geology of the Neolithic iron-aluminium phosphate mines of Gava, Catalonia [Aproximacion geologica a las minas neoliticas de fosfatos ferrico- aluminicos de Gava (Catalunya)]
Por:
Costa F., Camprubi A., Melgarejo J.C.
Publicada:
1 ene 1994
Resumen:
The mining complex of Gava, which contains the oldest underground mines found in Europe, was worked from 5400 b.p. until nearly 1000 years later (Neolithic). Geological mapping and a detailed mineralogical study was performed to investigate the mining techniques used. The geology of this complex consists of Llandoverian materials unconformably covered by up to 3 m of Quaternary calcretes. The Silurian series consist of grey shales with chert layers and nodules, monomineralic hematite, jarosite and Al-Fe phosphate layers. Post-Hercynian veins filled by variscite, turquoise, strengite and jarosite cut across the Silurian materials. Many of the galleries and pits run along phosphate veins or layers. Other galleries and chambers were made by the easy removal of materials affected by fracturing. Neither galleries nor pits are made along chert or iron oxides. Hence, the aims of exploitation were variscite and other similar phosphates for ornamentation. -from English summary
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