Calibre Mining Corp. is an exploration-stage company engaged in the acquisition, advancement and development of precious and base metal assets, and mineral properties. The Company focuses on the exploration of mining triangle in northeast Nicaragua, named the Borosi Concessions. The Borosi Concessions area has gold, silver and copper mineralization. During the year ended December 31, 2011, it focused its exploration of the Borosi Project on a range of targeted areas, which included Primavera Gold-Copper Discovery, Riscos de Oro Project, Rosita D Concession and Inferred Resource. The Primavera porphyry gold-copper discovery is located seven kilometers south of the Santa Rita mine in the Borosi Concessions of Northeast Nicaragua. Riscos de Oro prospect is located in the Eastern Epithermal Camp of the Borosi concessions and consists of gold-silver mineralization. During 2011, it completed Phase II diamond drilling program of 19 drill holes totaling 4,867 meters in Riscos de Oro Project.