Karakteristik Pengayaan Nikel - Kobalt (Ni - Co) Pada Endapan Nikel Laterit Pulau Pakal, Kecamatan Maba, Kabupaten Halmahera Timur, Provinsi Maluku Utara

Abstract

The increasing global demand for cobalt, projected to reach 390,000 tons by 2030, has drawn
growing attention to the potential of laterite deposits as strategic mineral resources, particularly
in ultramafic rock regions such as eastern Indonesia. This study was conducted on Pakal Island,
Maba District, East Halmahera, North Maluku. It aims to examine the geological conditions,
geochemical characteristics of nickel laterite deposits, and the enrichment of cobalt (Co) in the
study area. The methods employed include geological field mapping, rock sampling, and laboratory
analyses involving petrography, XRD, XRF, and SEM-EDX. The results show that the Dunit and
Harzburgit units contain olivine, orthopyroxene, and serpentine minerals. The limonite zone contains
hematite, goethite, and lithiophorite, while the saprolite zone contains garnierite and enstatite.
Co enrichment is predominantly found in the limonite layer (0.12–0.15%) and is influenced by
lithology, degree of serpentinization, topography, geological structures, and the tropical climate,
which accelerates chemical weathering. The vertical distribution of Co shows an inverse correlation
with Ni. These findings contribute to the understanding of the formation processes and
characteristics of nickel cobalt laterite deposits in eastern Indonesia and provide a scientific
basis for future exploration of cobalt-based strategic mineral resources