Dec 5 2014
West Melville Metals Inc. today announced that the first phase of the metallurgical test work being conducted on the Isortoq Project by the Commonwealth Scientific and Industrial Research Organisation (CSIRO) in Perth, Australia has been successfully completed.
- Positive metallurgical test results with scope for further improvements with optimization.
- A simple beneficiation process yields a clean, high grade concentrate (50.2% Fe; 20.9% TiO2 and 0.34% V2O5).
- Best leaching results achieved in the hydrochloric acid system, with separation of iron and vanadium from titanium (titanium remains in the leach residue)
- Leach efficiency of >95% for vanadium and >80% for iron, with >95% of extraction occurring within 30 minutes.
- These results represent the successful completion of the first stage in the development of a hydro-metallurgical process flow sheet aimed at commercially extracting iron, titanium and vanadium from the Isortoq deposit.
"We are encouraged by the results of this first phase of metallurgical test work," stated Dr. Rory Moore, CEO of West Melville Metals. "A simple beneficiation flow sheet has been demonstrated to produce a clean, high grade concentrate and the initial leach tests have shown that the Isortoq concentrate can be efficiently leached in relatively dilute hydrochloric acid. The CSIRO is now preparing a proposal for Phase 2 of the test work, which will include optimization of the leaching process, together with an evaluation of various methods for recovering high purity marketable titanium, vanadium and iron from the Phase #1 products."
An initial 25 kilogram representative sample of the mineralised body was crushed and milled to 120 microns and then subjected to a low intensity magnetic separation process with the resultant concentrate assayed for key chemical elements. Five separate leach tests were then completed using three different acid systems in order to establish the leaching characteristics of the concentrate. The leach tests were each undertaken for a period of 10 hours at a temperature of 90° centigrade at atmospheric pressure, with kinetic sampling of both leach liquor and residual solids over the duration of the test. Two tests were conducted using different concentrations of hydrochloric acid (28% and 21%), two with sulphuric acid (42% and 29.7% strength) and one test using nitric acid at 60% strength.
The results of the Phase 1 test work are positive with scope for further improvements with optimization. The simple beneficiation process yielded a mass pull of 50.8% to the magnetic fraction to create a clean concentrate that assayed 50.2% Fe; 20.9% TiO2 and 0.34% V2O5, which is notably higher than the grade achieved in previous beneficiation test work. With respect to the leach tests, some particularly encouraging results came from the hydrochloric acid system with selective deportment of vanadium and most of the iron into the leach liquor and titanium remaining in the solid residue. Extraction efficiency was >95% for vanadium and >80% for iron in the hydrochloric acid systems, with >95% of the leach extraction occurring within the first 30 minutes of the process. The separation of iron and vanadium from titanium in the initial leach is advantageous as it facilitates efficient extraction of titanium in a second leach or alternative extraction process. Results for the sulphuric acid system were also good with high extraction efficiencies for vanadium and iron; however, the sulphuric acid system did not provide as good of a separation of the titanium from the vanadium and iron compared to hydrochloric acid. The leach extractions in the nitric acid system were not as efficient as those achieved in the other two acid systems.
The Isortoq Project is a large iron-titanium-vanadium prospect located in southern Greenland. In 2013, the Company announced an initial National Instrument (NI) 43-101 inferred resource estimate for the Project of 70.3 million tonnes grading 38.1% FeO (29.6% Fe), 10.9% titanium oxide (TiO2) and 0.144% vanadium pentoxide (V2O5) applying a 15% iron cutoff. It is significant to note that this initial resource represents drilling on less than one kilometre of the Isortoq body while evidence from previous drilling and the 2012 ground magnetic survey has demonstrated a strike length exceeding 16.3 kilometres with the mineralized body being open to the south. The property is favourably located on a deep, ice-free ocean inlet on the temperate southern coast of Greenland within 60 km of Narsaq and 100 kilometres from Narsarsuaq International Airport. Bench scale beneficiation tests produced average concentrate grades of 50.2% Fe (71.8% Fe2O3); 20.9% TiO2 and 0.34% V2O5 with acceptably low levels of penalty elements S, P, Si, Al. These are positive indicators that support the future economic potential of the project.