Yamamoto, who also chairs Largo's audit committee, is registered as a panel auditor with the Investment Industry Regulatory Organization of Canada (IIROC), which enables her to conduct audits of investment dealers.

Sierra Metals chairman J. Alberto Arias said Yamamoto's appointment as an independent director of the Peru and Mexico focused metals company would "help Sierra Metals execute on its considerable growth plans and strategic opportunities that it has available at all its properties".