St George Mining (ASX:SGQ) began a metallurgical test work on the niobium-rare earths element mineralization at the Araxá project in Brazil as it plans to begin a drilling campaign, according to a Wednesday Australian bourse filing.

The initial scope is focused on optimizing niobium and rare earth recoveries via flotation processing, using samples selected from historical drilling at the project.

Future test work will focus on the two next steps in niobium production, refining the niobium concentrate by leaching and/or calcining as well as advancing towards the conversion of final niobium products.

It will also investigate new technologies for refining and conversion.