Premise: Miróbriga ("Mirobriga Celticorum") is an ancient Roman town located near the village and civil parish of Santiago do Cacém, in the municipality of the same name in the south-west of Portugal. Archeology revealed a that the town occupied the site of an ancient Iron Age settlement that existed since the 9th century B.C.
Hypothesis: Copper was found at the site of an ancient Iron Age settlement in south-west Portugal