Mamuju's Rare Earth Element Potential: A Future Industry and Ecological Vigilance

In the midst of the global race to master future technology, rare earth elements (REE) have transformed into a strategic commodity whose value far exceeds that of ordinary mining materials. REEs are the heart of various modern industries, ranging from electric vehicles and advanced electronic devices to renewable energy and sophisticated weapons systems. In this context, Mamuju Regency, West Sulawesi, is now in the spotlight. This region holds REE reserves believed to be among the largest in Indonesia, potentially forming a crucial foundation for the national ambition to build a strategic mineral downstream industry. Unlike many other areas that only possess REEs as associated minerals, Mamuju hosts primary deposits contained within the volcanic rocks of the Adang Formation. Its geological characteristics are also quite distinctive, as most are of the Ion Adsorption Clay (IAC) type associated with the weathering of phonolite leucite igneous rocks. This type is known to be relatively easier and cheaper to extract compared to other primary REE types. Exploration data from the Geological Agency of the Ministry of Energy and Mineral Resources indicates that REE grades in several locations in Mamuju reach up to 4,571 ppm. This content includes high-value elements such as neodymium, which is essential for making permanent magnets for electric vehicles, wind turbines, and various defence equipment. This potential places Mamuju on the national industrialisation map. President Prabowo Subianto has set a target for Indonesia to no longer be merely a raw material exporter but to be capable of producing downstream products based on REEs. To support this agenda, the government established PT Perusahaan Mineral Nasional (Perminas), which is planned to work on a pilot project for REE downstream processing in Mamuju. Central government has also begun encouraging various research and development of REE processing technology in the area. Several zones have even been proposed for special status as State Reservation Areas or People’s Mining Areas. Research results show there are at least three main blocks storing REE potential in Mamuju. The Botteng Block in Simboro District, covering approximately 1,011 hectares, is estimated to have inferred resources reaching 122,505 tonnes. Meanwhile, the 3,165-hectare North Botteng Block and the 1,659-hectare Ahu Pasabu Block also show promising REE content. Currently, REE development in Mamuju is still in the preliminary research and exploration phase. The area studied only covers about 10 hectares of the entire prospective area spread across several blocks. The biggest challenge lies in processing technology. Up to now, mastery of REE separation and purification technology is still dominated by China. Many developed countries, including the United States, still depend on China’s technological capabilities. Various universities, such as the Bandung Institute of Technology (ITB) and the University of Indonesia (UI), are still conducting laboratory-scale research to find technology appropriate for the characteristics of Indonesian REEs. Although the economic opportunity is substantial, the discourse on developing REE mines also raises concerns that cannot be ignored. The Indonesian Forum for the Environment (WALHI) West Sulawesi warns that some areas included in the mining development plan are located in regions with crucial ecological functions. Based on initial tracing, the Botteng and North Botteng areas are suspected to intersect with water catchment zones, hilly areas, community farmland, and water source routes that have been sustaining the lives of residents in Simboro District.