The Azul deposit is related to the Proterozoic Águas Claras formation, which is characterized by a progradational succession of platform sediments in the lower part and littoral and fluvial deposits in the upper part. The primary mineralization is hosted in a pelitic sequence on the basal portion of this unit (Azul member); and the secondary mineralization, which is considered the most important ore, is related to residual/supergene enrichment associated with a mature lateritic toposequence acting from at least the Upper Cretaceous throughout the Tertiary and Quaternary. The geologic sections exposed in the mining area show the presence of siltstones/pelites, fine red to white sandstones, and lens-formed layers made of gray siltstones to gray black shales, rich in carbonaceous organic matter and/or Mn oxi-hydroxides or rhodocrosite, characteristics of terrigenous/chemical and lateritic sources. Primary structures such as hummocky cross stratification and parallel laminations are common in these rocks. Bedding with a thickness of centimeters to a few meters (30 to 50 cm) represents the main primary structure. The lateritic profile is deep (100 m) and is characterized by differentiated horizons, which correspond to progressively upward physico-chemical degradation from a thick clayey horizon to nodular lateritic crust, breccia-like, cavernous, or massive. Large sectors of the mining area are covered by yellowish brown earthy to clayey material, with spheroliths concentrated at the base as a product of chemical and physical weathering of the lateritic profile, and deposited by gravity in paleodepressions or paleovalleys.

Structurally, the Azul deposit is located in the central portion of the Carajás Strike-Slip System (CSSS) with rocks organized in asymmetric folds cut by E-W trending directional/thrust faults and N-S trending normal faults, partitioned in different scales. The parallelism of the structural trends in the mining area and lineaments related to the CSSS suggests a close relation with regional deformations (dextral transtensional and sinistral transpressional episodes). Faults with normal kinematics associated with the dextral component of displacement are the major exposures in the area and are interpreted as related to the transtensional episode of the installation of the Carajás fault prior to 2.6 Ga. Folds, thrust faults, and subvertical fault zones would be related to deformation under the sinistral transpressional regime, a second event responsible for the reactivation and tectonic inversion of most of the primary structures near the Carajás fault zone.

Open-pit mining operations and on-site beneficiation plant.

The AMC presents excavations reaching a total height of 80 m, with 4 to 8 m bench height and 5 m berm width. A large waste pile is located along the northern border of mine 1 (waste pile north).

Crushing, scrubbing and classification steps, producing lumps and fines.

Manganese ore is transported by truck and EFC railroad to the Ponta da Madeira maritime terminal.