Privately-owned Gekko, which Sandy started with Elizabeth Lewis-Gray more than 20 years ago, is internationally recognised for its mineral processing plants and technology.

IOM3, which promotes and develops material science and engineering, said Sandy Gray had "rejuvenated the art of continuous gravity separation and become a world leader in low energy and pre-concentration flowsheets encompassing gravity methods, flotation, concentrate leaching for the gold and silver sector".

"His inventions are breakthroughs in the field of mineral processing … and are widely installed in operations throughout the world."

Accepting the award, Gray said he was "deeply honoured to receive international recognition on behalf of myself and my dedicated and talented team".