South Australia’s Four Mile Uranium Mine is of world-wide significance, says Premier Jay Weatherill.

He officially opened the mine’s first stage on Wednesday and congratulated the joint venturers, Quasar Resources Pty Ltd and Alliance Craton Explorer Pty Ltd.

“This is one of the most substantial uranium discoveries anywhere in the world in the past 25 years,” he said.

“The project has already involved a private sector investment of more than $120 million and demonstrates the strength of the South Australian mineral resources and energy sector.”

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The initial stage of mining operations will collect information and assess mining conditions of the Four Mile east section.

Heathgate, an affiliate to joint venturer Quasar Resources, will provide services to the mine and operation of its nearby plant.

Mr Weatherill said Heathgate employs 140 people and actively promotes employment opportunities to the Adnyamathanha people.