Name of the Mine
São Chico mine.
Location
Tapajos region in the state of Para, in Brazil.
Mine Owner/s
Serabi Gold.
Brief Description
The São Chico orebody is a satellite deposit providing supplementary high-grade gold ore to Serabi’s Palito processing plant to increase the company’s overall gold production
The mine’s current resources are identified in three vein structures – the Main vein, the Parallel vein and the Julia vein – covering a strike length of about 900 m.
Brief History
Commercial production was declared at São Chico orebody in January 2016, following the construction of a mine portal in 2014. The portal was established in September 2014 and during the fourth quarter of that year, the decline ramp was advanced towards the first two underground development levels.
The main vein was intersected in January 2015, and by the end of December 2015 the ramp development provided access to three development levels and the production of ore from the first stopes started.
Primary Metals/Minerals
Gold.
Secondary Metals/Minerals
None stated.
Geology/Mineralisation
São Chico is a shear-hosted gold deposit.
Outcrop at São Chico is meagre owing to widespread laterite development and alluvium. The cover comprises a red, lateritic top soil between 1 m and 3 m deep, with a lower boundary evident in a stone line or pesolith of quartz fragments and ferruginous pebbles. Quartz float at surface overlies quartz vein zones.
Early to Middle Proterozoic granite and granodiorite of the Pararauri Suite lies beneath the São Chico deposit. Host rocks comprise granodiorite and granite, typically medium-grained, leucocratic, feldspar phyric and belonging to a larger, poorly exposed intrusive complex.
Mineralisation is hosted in west-north-west-trending, steeply south-dipping fault zones, with a shear component. These mineralised faults have been offset by north to north-north-east-trending normal faults, with a dextral lateral displacement.
Reserves
Total proven and probable reserves as at December 31, 2020, were estimated at 44 312 t grading 6.12 g/t gold.
Resources
Total measured and indicated resources as at December 31, 2020, were estimated at 479 245 t grading 5.37 g/t gold. Inferred resources were estimated at 608 129 t grading 4.81 g/t gold.
Mining Method
Sublevel open stopping.
Major Infrastructure/Equipment
Serabi operates a 500 t/d plant to process ore from its São Chico and the Palito mines.
The São Chico is amenable to direct cyanidation and following crushing and milling, the mine ore passes through a gravity concentration circuit with the concentrate produced being passed through an in-line leach reactor, where gold is leached and then recovered through conventional electrowinning and smelting processes to produce bars of gold doré.
The tailings from this process continue to pass to the carbon-in-pulp recovery plant where they are blended with the Palito flotation tailings.
Prospects
In the immediate proximity of São Chico’s Main and Julia veins, drilling has identified the Highway, Crossroads and West veins all of which could, in time and subject to further evaluation, be accessed by cross cuts from the existing mine workings.
Meanwhile, further to the west lie the Abelha, Besoura and Cicada anomalies where the results of induced polarisation have highlighted potential for sulphide mineralisation and evidence of past artisanal activity.
Contact Details
Serabi Gold
Tel +44 20 7246 6830
Email contact@serabigold.com
Website https://www.serabigold.com/
Sources
Serabi Gold. Annual Report and Accounts 2020.
Serabo Gold. Website: https://www.serabigold.com/ [accessed May 11, 2022].