In the Republican period metalworking shop evidence has been found of work with different metals and alloys such as iron, lead, bronze, brass, cinnabar, silver and gold. It is precisely the last two that are of particular importance, as on the Iberian peninsula few gold and silver working shops are known from this period, especially at this time.

The workshop was spotted and confirmed on the basis of finding microparticles in the crucibles unearthed in the building, proving beyond a doubt that they were used on this spot. The gold particle displayed a deliberate alloy of 72% gold, 16% copper and 12% silver, i.e. an artificial 18/17-carat gold. One of the silver particles contained 90% silver and 10% copper, also a very common alloy of worked silver. Among the remains some particles of mineral silver also appeared, i.e. not processed.

All this proves that precious metals were worked on at Castellot, using highly advanced metallurgical technology (alloys like brass were a Roman innovation, as was the use of cinnabar), which were unlikely to come from the Cerretanians and must be linked to the Roman military presence.

This gold and silver-working documented at Castellot gives rise to some significant considerations:

  • We know of the existence of alluvial gold particles in the Miocene deposits of the Cerdanya region.
  • We have been able to document the exploitation of these gold deposits in ancient times in nearby areas (Les Guilleteres d’All). We also know they were exploited during the Islamic period.
  • The discovery of a gold earring on the same site in a Republican context would seem to indicate this activity.
  • The recovery of traces of cinnabar, a mineral needed to amalgamate gold and also used to gild objects in antiquity, and very probably traded from the mines of Almadén (Ciudad Real), reveals activity of an intensive nature that must once again be linked to the Roman presence.
  • The unearthing of pieces of gold on other ancient sites in Cerdanya very close to Castellot, such as El Baltarga or the necropolis of Prats, shows that this activity went on over time.
  • It must therefore be supposed that the Castellot workshop shows not only gold and silver working on the site, but also the exploitation of the mineral resources of the Pyrenean region, especially alluvial gold, but probably silver too.

Image 1: Earring found in Building II at Castellot.

Image 2: Gold particles recovered from crucibles in the metal working shop.

Image 3: Gold particles from the Miocene deposits in Cerdanya.