Day

With 8.60 grams of gold per tonne, the test "yielded significantly more ounces of precious metals than we estimated," said CEO Ari Sussman.

Argos and Holcim have issued statements denying any wrongdoing and said that they disagree with the findings of Superindustria.

CEO Rubens Amaral will step down on April 30 and be replaced by N. Gabriel Tolchinsky. CFO Christopher Schech will be replaced by Ana Graciela de Méndez

Ecopetrol has a 50% stake in the discovery, which is lighter than typical heavy Colombian oil, according to the company.