The Marzano-Velasquez clan lived a simple…life on a mountain that turned out to hold the world's largest known copper-and-zinc deposit…[T]hey…believe[d] the open-pit Antamina mine [joint venture of BHP Billiton, Glencore Xstrata, Teck & Mitsubishi Corporation] would lift their…highlands district from poverty, provide steady jobs, decent health care and schools…While colossal copper, gold, lead, tin and silver pits helped Peru's economy more than double in size, the people in the rural highlands that they dominate have been…left behind, battling one environmental disaster after another as expanding mines contaminated their water, air and livestock…On the edge of Antamina's nearly half mile-deep pit, blasts hurl skyward a blood-orange dust that laces the village of Juprog's fields with heavy metals, contaminating people, crops and livestock…Antamina's land and resettlement director, Mirko Chang, said the dust cloud is not toxic…He said Antamina carefully monitors the air quality — but declined to release those test results…