Study on the Critical Metal and Rare Earth Element Occurrences in Sulawesi

Abstract

As the development of modern-high technology application is growing, demands of the constant supply of Scandium (Sc) and rare earth elements (REE) as a new green source of energy is increasing. Meanwhile, source of these elements are limited hence new source of these minerals have to be found. Nowadays, Scandium (Sc) is an important metal for electrolyte of solid oxide fuel cells and the demand is likely to increase in the near future. In addition, REE is an important element in the use of permanent magnets and rechargeable batteries. Exploration on critical metals and rare earth element in Indonesia is still scarce due to lacking of skillful human resource who understand about the occurrences and distribution of these elements. Based on the most update investigation, critical metal particularly Scandium can be found in weathering crust of highly weathered nickelcontained ultramafic rock. Scandium will be concentrated in limonite and saprolite layer, but the volume of enrichment is still unknown. Meanwhile, rare earth element found in granitic rocks particularly in zircon, monazite and xenotime. It has been reported that rare earth ore were extracted from heavily weathered granitic rocks. Sulawesi Island is one of the island where lateritic deposit from heavily weathered ultramafic can be found. The lateritic soil can be potential source of scandium. Meanwhile, granitic rocks cover almost 20% of the island which also potential source of rare earth element. These suggest that Sulawesi Island has a big potential and challenge for critical metal and rare earth element exploration. This manuscript reports the exploration potential and challenge of critical metal and rare earth element in Sulawesi based on geological data.