Access to the Espérance mine is by river, via the Maroni River which borders the border with Suriname. An aviation runway of nearly 1000m provides easy access to the site.
The operation, which has been completed since 2010, was an open pit mine (OFM). It was carried out using Hyundai 450 mechanical excavators (4 units) and the transport of the ore by Terex TA35 articulated dumpers (4 units). The company only exploited soft saprolitic materials that do not require explosive felling.
The ore was processed in two stages: crushing and grinding in two closed-circuit ball mills. The gold recovery was then ensured by centrifugal concentrators of type Knelson KC 48.
Esperance Creek has been known since 1890 for its wealth of gold. Various works were undertaken by the former gold miners who left traces of their passage on site: tunnels, railway, steam engine, etc.
During the inventory of Guyana’s mineral resources, the BRGM will carry out significant work covering the work of the elders. The results are surprising, showing a geochemical anomaly more than 2 km long and 500 m wide. The three cored boreholes drilled in the process show a mineralization rooted in saprolite and hard rock up to at least 150 m of depth.
The deposit then emerges as a priority N°1 of the inventory.
At the end of the 1980s, Gérard Ostorero discovered this project with interest and quickly gathered the necessary resources to put it into operation. He founded Compagnie Minière Espérance in 1991, after obtaining a personal research permit.
Mining begins with the alluvial resource, which is abundant and provides funding for the development of the Espérance primary mine.
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In Espérance, mineralization took place in tectonic contact between the Maroni sedimentary basin and a set of granite massifs. The basin is formed by detritic series, resting in discordance on a volcano-sedimentary base (series called «Paramaca»). The affected area is strongly deformed by the shear movements that developed in contact with the granites.