West Perth-based mining company Sphere Investments Ltd has completed a pre-feasibility study on its Guelb el Aouj iron ore joint venture in Mauritania, with an estimated total capital cost of $1.86 billion.

West Perth-based mining company Sphere Investments Ltd has completed a pre-feasibility study on its Guelb el Aouj iron ore joint venture in Mauritania, with an estimated total capital cost of $1.86 billion.