The Pilar and Roça Grande deposits are examples of the Algoma BIF-hosted type. The main geological characteristics of this group are summarized as follows:

- Main host/fertile “Algoma-type” BIF Units: These units host the mineralization and are stratigraphically located at the waning stages of major volcanic cycles of the Rio da Velhas greenstone belt.

- Mineralization style: The mineralization consists of mainly “lateral” replacements/sulphidations of the iron carbonate-rich bands of the host Algoma-type BIF units. However, the BIF-hosted gold mineralization is not syngenetic in nature (in relation to the deposition of the host rock packages), rather it is clearly an epigenetic event that has occurred after the formation of the host rock units.

- Dimensions of the economic orebodies: Economic strike-lengths of only 50 m to 350 m for individual mined zones. Average thicknesses of the BIF-hosted orebodies may range from 2 m to 20 m.

ROÇA GRANDE DEPOSIT GEOLOGY
The Roça Grande Mine is located in the upper unit of the Nova Lima Group. The dominant rock types found in the mine are a mixed assemblage of meta-volcanoclastics and meta-tuffs. These are represented by quartz sericite and chlorite schists with variable amounts of carbonate facies
BIF, oxide-facies BIF, meta-cherts, and graphitic schists. The iron formations, chert units, and graphitic schist units are intimately inter-bedded with each other, such that they form ........

The Caeté Gold Mine Complex has two underground mines: Pilar Gold Mine (“Pilar”) and Roça Grande Gold Mine (“RG”). On March 22, 2018, the Roça Grande mine was placed on care and maintenance.

At Pilar, gold mineralization is contained within a shear zone with an average 50º to 60º dip. The mineralization is structurally complex due to intense folding and displacements (up to 2 m) due to local faulting. This results in direction changes and pinching and swelling of the ore zones over relatively short distances. The ore zones hangingwall (HW) and footwall (FW) contacts with the non- economic wall-rocks are almost everywhere visible by eye, though sampling shows that there are, on some occasions, a few surprising assay results (variable gold grades) within the ore-hosted BIF formation. The orebody is approximately 250 to 350 m along strike, and the orebody is accessed and mined along strike via crosscuts perpendicular to the orebody.

Mining Methods
Two mining methods are utilized at the Pilar operation: Cut and fill, that represents about 10% of the mining fronts, and Sublevel, that represents about 90% of the mining fronts. The Cut and Fill method is utilized for individual orebodies with irregular geometry and/or for individual orebodies that dip less than 45º; while the Sublevel method is utilized for thicker orebodies that dip more than 45º. The current LOM forecasts the Sublevel method as the largely predominant one at the Pilar operation in the ........

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