Dundee Sustainable Technologies Inc. and Radisson Mining announced the results of a pilot scale metallurgical test program utilizing DST's arsenopyrite treatment approach, on a 5-tonne sample from Radisson'sO'Brien gold project. DST successfully removed 92.2% of the arsenic content and demonstrated, at the pilot scale, that the refractory parcel of O'Brien gold material can undergo a pre-treatment to remove arsenic and create a mineral concentrate with levels of arsenic that are acceptable to the market and traditional gold recovery circuits. In February 2017, DST received 5 tonnes of representative material from the O'Brien gold project.

The material was crushed and ground. The free gold was recovered by gravimetry and the balance of the material was concentrated through flotation. This approach mirrored Radisson's planned recovery circuit in the PEA.

DS generated a gold concentrate which contained 109 grams per tonne of gold, 11.6% arsenic and 19.9% sulphur. Using's DST thermal decomposition in an oxygen deprived environment approach, the arsenic content was reduced by 92%, with no gold losses while leaving a sulphur content of 8%. The arsenic depleted concentrate was treated for gold extraction using both DST's patented chlorination technology and cyanidation where gold recoveries of 94.6% and 93.5% were achieved, respectively.

The process was overseen by an independent consulting firm so that the piloting test program and results could be included in Radisson's future Preliminary Economic Assessment (PEA).