Latest metallurgical test-work has delivered a 95.2% gold recovery result using a conventional gravity and flotation circuit at the 500,000oz Labyrinth Gold Project in Quebec, Canada.

These results will underpin optimisation studies, initial plant design costings and assessment of any third-party ore sales, toll treatment or concentrate sale – which are already underpinned by a resource grade of 5g/t.

The project commenced in August with the submission of diamond core crushed residue composites to Base Metallurgical Laboratories in British Columbia, Canada with the overarching aim being to define the key mineralogical characteristics of the likely mill feed to a future plant.

According to Labyrinth Resources (ASX:LRL), metallurgical test work was also designed to reflect likely flowsheets being gravity/cyanidation and gravity/flotation/cyanidation, conduct comprehensive assays and mineralogical analysis, and process streams for flowsheet optimisation and marketing purposes.

The nitty gritty

BaseLabs were presented with a total of 35 diamond hole crushed residue composites totalling 17.55m at 6.32g/t gold, which originated from a total of five diamond holes representing at least 50% of the known gold mineralisation of the project and reflects the 7g/t gold resource feed grade.

Five sub-composites were generated initially for assay prior to producing a single Master Composite which returned 5.60g/t gold and 1.7g/t silver via BLEG assay.

Not only did the mineralogical studies confirm the production of a pyrite dominant concentrate but initial BLEG test work on the Master Composite returned a cyanide recovery of 97.1% gold and 99.7% silver, suggesting the ore is free milling.

What’s next?

LRL says opportunities to further improve flotation and dissolution kinetics and to reduce capital and operating cost will be the focus of future studies including the application of the baseline conditions identified in this program to variability diamond core samples.

The company believes it is in a strong position based on these standout metallurgical results to conduct a preliminary economic study on the following three options:

  • Installation of a Gravity/Float/UFG Leach circuit;
  • Installation of a Gravity/Float circuit for offsite sale/treatment of float concentrate; and
  • Whole of Ore Toll Treatment or Ore Sales through discussions with nearby facilities.



This article was developed in collaboration with Labyrinth Resources (ASX:LRL), a Stockhead advertiser at the time of publishing.  

This article does not constitute financial product advice. You should consider obtaining independent advice before making any financial decisions.