"I see tremendous potential in the Sugar Zone property and believe the operational challenges experienced to-date can be resolved," Coetzer, the former Golden Star president and CEO, said.
"Upon Martin and I taking office, our near-term focus is to drive stronger operational performance, optimize underground operations, ensure the paste plant is operational by year end and execute a 2020 mine plan and strategy that is achievable."
Raffield, chief technical officer and executive vice president at Golden Star, and a former US practice leader with leading global mining consultancy SRK, is now executive VP and chief operating officer at Harte.
The company's only mine, near the major Hemlo gold camp, produced 7,754oz at AISC of C$1,734/oz in the June quarter. Harte has been targeting 39,000oz at US$1,300-1,350/oz this year and 65,000oz at US$913/oz in FY2020.
Coetzer's plus-30 years in mining included the time at Golden Star during which the company transitioned from surface to underground production on Ghana's Ashanti gold belt, as well as senior executive and operations roles with Kinross Gold, Xstrata Nickel, Xstrata Coal and Placer Dome. The mining engineer got his engineering degree from the University of Pretoria in South Africa.
Raffield, a veteran of 25 years in mining, has extensive experience managing underground mines in Canada and Africa. He has a PhD in geotechnical engineering from the University of Wales and is a professional engineer registered in Ontario.
Harte Gold shares (TSX: TSE) have more halved in value since the start of 2019, capitalising the company at C$122 million. They dipped 20% Monday.