Minea are people who seek out rare Metals or Ores at the risk of their own life, and they are highly respected. A Minea is equivalent to a hero. They seek rare metal at the cost of their lives. Without them the Rare Metal Industry which drives the world's current ecnomomy would never exist. Mineas appears to be very wealthy.
Luca mention he will become a Minea. But the villagers of Elza Village laughed at his dreams. They told them that Minea regularly getting amounts of life indemnity. They own a lot of houses some even own islands.