On February 26, 2020, Fengro Industries completed the previously announced disposition of Fengro’s Brazilian assets (Brazilian fertilizer business) to Gefoscal Comércio, Indústria, Representações e Transporte de Produtos Agropecuários Ltda.
The Transaction included the sale of Dusolo Mineração Ltda., a subsidiary of Fengro, which owns 100% of the Bomfim Project.
Summary:
The Bomfim Project is within a large package of rocks along the western edge of the São Francisco craton and immediately east of the Brasilia fold belt in central Brazil.
DuSolo holds the mineral exploration rights to seven exploration licences within the region. Together, these licences compose the Greater Bomfim Project; however, this report (PEA 2016) deals with the information that was acquired during the work that was undertaken with respect to DNPM administrative instrument 864.494/2012, which corresponds to the Santiago, Tataco and Pombo targets. These targets compose the DANF Santiago Project.
Mineralization
Mineral exploration work and exploratory drilling was intensified since the last report. Re-interpretations were undertaken and, because of the various types of mineralization present, which display a large range of phosphate concentrations, the mineralization was separated into two principal groups: high grade (HG) and low grade (LG).
A value of =10% P2O5 was adopted for the DANF Santiago Project in order to designate the HG mineralization, which was referred to as the phosphorites group. Rocks that contained concentrations below that value, but above 3% P2O5, are referred to herein as LG mineralization, which are simply referred to as phosphatic rocks. The company has studied and continues to study processes for the separation and concentration of the low-grade material, which would increase the economic potential of the LG mineralization in the deposit. Although the literature defines phosphorite as having grades that are quite higher than those that were adopted by the company, the limit of 10% that was applied herein sought to provide objectivity and be compatible with the processing routes that were evaluated.
High grade (phosphorite): The rocks that are included in this group can be separated into brecciated, laminated and clayey phosphorite.
Low grade (phosphated rocks): Within the study area, this category of rock is the most abundant. These rocks include various kinds of siltites that vary from being solid to having either parallel or wavy lamination. They are friable, heavily weathered and have brown and yellow colorations (Figure 7.3_4). The presence of manganese is very common within the planes of micro-fissures, as well as along the laminae. It was shown that certain pores contained apatite. These rocks differ from the phosphorites in their friability and low densities.
Mineralization at Bomfim is classified as of a shallow nature, restricted to nearshore environments. These giant phosphorites generally formed in distal shelf environments in association with coastal upwelling (Pufahl 2010). At Bomfim, storms waves and tidal currents swept the seafloor and flood channels, re-working the pristine phosphorite producing phosphatic intraclasts that can be concentrated into beds or lags. Depending on the degree of re-working granular phosphorite can be matrix or grain supported (Pufahl 2010). Later, uplift and erosion exposed the phosphatic sediments, tropical weathering leads to lateritization, which process removes some minerals and results in the concentration of residual elements, including phosphorus.