Phosphate was first discovered in one geotechnical drill hole as part of a water survey in 1950 and noted again in one oil drill hole by Esso in 1965. The French Bureau of Geological and Mining Research (BRGM) conducted an extensive exploration and delineation drilling program from 1981 to 1983, during which time they drilled 5,672 m of large diameter core in 101 holes. This enabled them to carry out a detailed geological study of the deposit and provided a comprehensive database for the French agency Sofremines to conduct a prefeasibility study in 1986. The prefeasibility study was positive but market conditions and political considerations precluded development at that time and the French agencies withdrew from the Project.
In 1997, Champion Resources of Canada, acquired ownership of the Farim phosphate deposit and carried out diamond drilling campaigns in 1998 and 1999 totaling 1810 m in 34 holes. The main purposes of the Champion drilling were to confirm the BRGM results for due diligence purposes, to provide fresh phosphate samples for metallurgical test work and to expand the phosphate resource to the west. The programs were successful in that all three goals were achieved. Champion Resources Inc. carried out a prefeasibility study which again demonstrated that a phosphate mining and beneficiation project was economically viable. However, no further progress was made due to both internal political and external market conditions and phosphate rock prices.
In 2006, GB Phosphate Mining Ltd. was granted, by the Government of Guinea-Bissau, mineral rights over the Farim phosphate deposit and evaluated its potential. They undertook several comprehensive studies including excavating a box cut drilling 30 holes to confirm and validate the work of previous explorers, a hydrological study, an environmental impact study and an economic evaluation of the Project. In 2009, the Government of Guinea Bissau granted to GB Minerals AG (“GBM AG”), now a wholly-owned subsidiary of GB Minerals Ltd., Mining Lease 004/2009 and Production License 001/2009, both covering 30,625 ha (“Concession Area”). The Government of Guinea Bissau and GBM AG also entered into a mining agreement to govern the execution of Mining Lease 004/2009 and Production License 001/2009 and to clarify the framework applicable to the development of the Project.