The country has rich iron resources as well as some diamonds, gold and other minerals in ancient sediment formations weathered to higher concentrations by tropical rainfall.
Greenstone belts, sequences of metamorphic and volcanic rocks associated with cratons and used by geologists to study early tectonics are found in south-central Liberia, dating to 2.1 billion years ago.
The clastic sedimentary rocks Gibi Mountain Formation, 32 kilometers north of the Todi Shear Zone form two heavily forested hills, lying unconformably on top of Archean gneiss.
Based on similarities between the Gibi Mountain Formation and the Rokel River Group in Sierra Leone, it appears that it formed between the late Neoproterozoic and the Cambrian.
Laterite soils formed as rainfall slowly leached away silicates, a process known as laterization, leaving highly enriched medium and high-grade ores.
Because of political turmoil and violence, most diamond mining is limited to alluvial digging near the border with Sierra Leone and to date, there has not been extensive exploration for offshore placer deposits.