The Santa Cruz graphite project is an open-pit graphite mine planned to be developed near Itabela in southern Bahia, Brazil.
South Star Mining, which was previously known as Stem 7 Capital, is the owner and developer of the project.
South Star Mining announced positive results of a pre-feasibility study (PFS) along with maiden reserve estimate for the project in February 2020.
With an estimated capital expenditure of £26.5m ($34.5m), the Santa Cruz graphite project is expected to produce up to 25,000 tonnes (t) graphite concentrate a year over a mine life of 12 years.
The Santa Cruz graphite project was previously undertaken by Brasil Grafite, a wholly-owned subsidiary of Brazil Graphite Corporation.
South Star Mining filed a preliminary economic assessment (PEA) on the project in December 2017 and completed the acquisition of Brazil Graphite in June 2018.
Location and geology
The Santa Cruz graphite project comprises 13 approved exploration licenses covering a total area of approximately 13,000ha.
The graphite deposit is situated on the Kinzigite migmatitic rock complex within the Aracuai Orogen that extends from the eastern edge of the Sao Francisco craton to the Atlantic margin, in south-eastern Brazil.
The Santa Cruz deposit is believed to contain one of the biggest flake graphite reserves in the Americas.
Santa Cruz graphite reserves
The Santa Cruz graphite project is estimated hold 12.3 million tonnes (Mt) of proven and probable ore reserves containing 295,400t of graphite concentrates.
Staged development plan
The graphite project is planned to be developed in two stages with phase one involving a small open-pit mine and a pilot processing plant capable of producing 5,000 tonnes per annum (tpa) of graphite concentrates.
South Star Mining received environmental permit for the pilot plant construction and operation in March 2020.
The production is planned to be ramped up to 25,000tpa from the third year of the mine’s operation in phase two.
The capital expenditure for stage one and two are estimated to be £5.6m ($7.3m) and £21m ($27.2m) respectively.
Mining and ore processing
The Santa Cruz graphite project will be a conventional open-pit mining operation. The mining fleet will include hydraulic excavators, dozers and haul trucks.
The run-of-the-mine (ROM) ore will be processed at an onsite facility for the production of graphite concentrate.
The process flow sheet for the graphite project will be tested and optimised based on the pilot plant operations.
The Santa Cruz project will utilise filtered tails technology and co-disposal of tailings with waste-rock, without requiring a tailings storage facility
The Santa Cruz project area can be accessed via via 90km of paved federal highways from the International Airport of Porto Seguro, Bahia.
The electricity for the project is proposed be supplied through a 1.6km-long 13kV high tension power line connecting an on-site substation.
The project also has the option of sourcing natural gas from the GASENE pipeline which runs approximately 5km away from the site.
Process water supply for the project will be provided from on-site sources either through wells or through a small water dyke to capture and store basin inflows.
Dompieri Tecnologia em Mineracao (DTM) provided the resource estimate as well as prepared the technical report for the Santa Cruz graphite project.