Canadian Mining Journal


GOLD: Bonterra tests reach 99.4% recovery, including 76.1% in gravity circuit

Checking core at the Gladiator gold deposit east of Val d’Or, Que. (Image: Bonterra Resources)

QUEBEC – Vancouver-based Bonterra Resources reports that recoveries of up to 99.4% gold have been reached during metallurgical tests using material from it Gladiator gold deposit 170 km northeast of Val d’Or. The gravity circuit alone recovered 76.1% of the gold, indicating a high free gold presence in the ore.

Head assays for the tests ranged from 8.0 g/t to 10.0 g/t gold. Using a combination of gravity and gravity-cyanide tests, recovery rates of 99.0% to 99.4% were achieved. The combination of gravity and gravity tails flotation tests yielded recoveries in the 96.8% to 97.3% range. That indicates that a cyanide leaching circuit may not be needed to achieve high gold recovery.

Said VP operations Peter A. Ball: “The simple metallurgy, consisting of potentially only a crushing and grinding circuit to achieve 76.1% recovery, provides a low capex/opex process to pour gold bullion on site. Adding a flotation circuit could yield up to 97.3% recovery and deliver a very high grade gold concentrate, making material very compatible and easily transported to a local or a centralized standard milling facility.”

Bonterra is current engaged in extension and resource expansion drilling at Gladiator with a resource estimate planned for the second half of this year.

More information maps and a  photo gallery of the Gladiator project is posted at