Tasman Precipitates Heavy Rare Earths Concentrate

Tasman Metals Ltd. (TSXV:TSM) announced that as part of the hydrometallurgical testwork program taking place on its Norra Karr heavy rare earths project, a heavy rare earths-rich concentrate has been precipitated.

As quoted in the press release:

Preparation of this concentrate is the final step in defining the Norra Karr flowsheet, and marks a significant milestone in the Company’s metallurgical programs. An update on recent beneficiation progress is also provided.

Beneficiation and hydrometallurgy testwork has been completed by various internationally recognized laboratories and delivered data of a quality suitable for the Norra Karr Pre-Feasibility Study (PFS) which remains in progress.

Highlights include:

• Crushing and grinding characteristics of the Norra Karr mineralized material are now well known. A grind size of 60 micron has been chosen which provides adequate liberation of the REE-bearing mineral (eudialyte) that can easily be achieved through standard commercial equipment;
• Extensive testwork and optimization of single-stage magnetic separation has been completed by equipment manufacturer Metso Minerals and metallurgical laboratories of the Geological Survey of Finland (GTK). This optimization has increased REE recovery in beneficiation to in excess of 86% in less than 35% of the original mass, such that flotation is no longer deemed necessary as was envisaged under the Norra Karr Preliminary Economic Assessment( PEA) published June 2013. Magnetic separation shall use standard commercial equipment and does not require process chemicals;
• Extensive hydrometallurgical research has been completed by ANSTO Minerals which has tested/optimized a process of sulphuric acid leaching, leach solution purification, REE solvent extraction and precipitation of an REE-concentrate. Sulphuric acid was chosen due to its relatively low cost, and its widespread availability in Sweden. A railway line which passes only 25km from Norra Karr already transports bulk sulphuric acid;
• Under the hydrometallurgical process developed, leaching is undertaken at ambient temperature and pressure. High temperature roasting is not required to dissolve eudialyte.

Click here to read the full Tasman Metals Ltd. (TSXV:TSM) press release.