Calibre Intersects 11.05 G/T Gold And 72.30 G/T Silver Over 2.30 Metres At The Borosi Gold-Silver-Copper Concessions, Nicaragua

June 30, 2010

Vancouver, British Columbia: Calibre Mining Corp. (TSX-V: CXB) (the "Company" or "Calibre") is pleased to announce additional high grade gold and silver assay results from its continuing drill program on both the Riscos de Oro and La Luna epithermal gold-silver projects within the 100% owned Borosi Concessions in northeast Nicaragua. Highlights of the drilling include 11.05 g/t gold and 72.30 g/t silver over 2.30 metres in hole RD10-003 from Riscos de Oro and 5.08 g/t gold and 36.65 g/t silver over 2.0 metres in hole LL10-006 from La Luna.

Robert Brown, President and CEO stated: "The results from Riscos de Oro drilling now confirm the continuity of mineralization to a depth of 210 metres below the historical workings, while results from La Luna have confirmed the mineralization of the La Luna vein system over an 1100 metres strike length and to a depth of 106 metres. Of the 10 drill holes completed to date on the Riscos de Oro and La Luna targets 8 holes or 80% have intersected significant widths and grades of gold-silver mineralization verifying the extensive and robust nature of these precious metal systems. Both zones remain open along strike and at depth."

Table 1: Highlights of Borosi Diamond Drilling Results

Project Drill Hole From (m) To
(g/t Au)
(g/t Ag)
Riscos de Oro RD10-002 205.40 210.30 4.90 0.97 28.72
  including 207.40 209.40 2.00 1.77 56.40
  RD10-003 296.30 299.70 3.40 8.81 55.74
  including 297.40 299.70 2.30 11.05 72.30
La Luna LL10-004 110.72 117.00 6.28 1.63 13.61
  including 110.72 113.00 2.28 2.11 13.49
  LL10-006 127.00 131.00 4.00 2.77 19.38
  including 129.00 131.00 2.00 5.08 36.65
    137.60 140.50 2.90 0.85 22.46
  LL10-007 18.95 20.70 1.75 2.99 30.66
    113.70 117.05 3.35 2.40 4.91
    116.39 117.05 0.66 7.14 8.66

Drill Holes LL10-003, LL10-005 did not contain significant results.

Riscos de Oro Project

Riscos de Oro is a northeast trending, low sulphidation epithermal gold-silver quartz vein system that has been traced on surface for over 2.0 kilometres. Riscos de Oro was previously mined by both open pit and underground methods from 1972 through to 1981. The main ore shoot at Riscos de Oro was only mined down to an approximate depth of 93 metres below surface and along strike for 300 metres. Calibre's first drill hole at Riscos de Oro (RD10-001 results released June 1, 2010) successfully intersected this zone at a vertical depth of 155 metres below surface and confirmed the continuation of high grade gold and silver. Two additional drill holes (RD10-002 and RD10-003) have both intersected the main Risco's ore shoot at a vertical depth of 200 metres and 275 metres respectively, and confirm that mineralization within the Riscos main ore shoot extends from surface to 355 metres down dip. Highlights from this drilling include 11.50 g/t gold and 72.30 g/t silver over 2.30 metres (RD10-003). The Riscos quartz vein system is open at depth and along strike. Four additional drill holes are scheduled to be completed on the Riscos de Oro vein system during the current drill program.

La Luna Project

La Luna is a northwest trending, gold and silver bearing, epithermal quartz vein system which has been delineated for over 2.0 kilometres through a soil sampling and trenching program. The initial drill hole (LL10-002 -- results previously released June 1, 2010) confirmed the depth extent of mineralization below a small historic open cut in the southern zone. A second drill hole (LL10-004) was drilled underneath LL10-002 to further test the depth extent of mineralization and successfully intercepted the quartz vein returning 1.63 g/t gold over 6.28 metres at a vertical depth of 110 metres below surface.

The strike extent of La Luna has been tested by a series of drill holes on 250 metre fences along an 1100 metre north west trending ridge. Hole LL10-006, 1082 metres north of LL10-002, returned encouraging results of 5.08 g/t gold and 36.65 g/t silver over 2.0 metres at a depth of 115 metres below surface, while Hole LL10-007 successfully identified two mineralized zones; one zone within 15 metres of surface returning 2.99 g/t gold and 30.66 g/t silver over 1.75 metres and the second at a vertical depth of 100 metres returning 2.40 g/t gold over 3.35 metres. Four additional drill holes are scheduled to be completed on the La Luna vein system during the current drill program.

Borosi Concessions

The Borosi concessions cover approximately 71,000 hectares within the historic Mining Triangle of Nicaragua. The concessions are subject to an option agreement, whereby B2Gold Corp. may earn an initial 51% in the Borosi concessions by completing C$8 million in exploration expenditures over a period of three years. Calibre and B2Gold have agreed to extend the C$2.5 million year one expenditure commitment to October 1, 2010; Calibre remains as operator.

Quality assurance and quality control procedures include the systematic insertion of blanks, standards and duplicates into the soil and rock sample strings. Samples are placed in sealed bags and shipped directly to ALS CHEMEX labs in North Vancouver, BC for gold fire assay and ICP multi element analyses. The technical content in this news release was read and approved by Roger March, P.Geo., a professional geologist registered in the Province of Newfoundland & Labrador and a qualified person as defined by NI 43-101.

Calibre Mining Corp. is an aggressive, well financed, TSX Venture Exchange listed company (TSX.V: CXB) that is focused on the acquisition, exploration and development of gold and copper deposits in Central America. Major shareholders of Calibre include gold producers Yamana Gold Inc. and Kinross Gold Corp.

Calibre Mining Corp.

Signed "Robert Brown"

Robert D. Brown, B.Sc., MBA
President and CEO

For further information contact:
Robert Brown -- Vancouver, Canada
604 681 9944

Neither TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.

Cautionary Note Regarding Forward Looking Statements
Safe Harbor Statement under the United States Private Securities Litigation Reform Act of 1995: Except for the statements of historical fact contained herein, the information presented constitutes "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995. Such forward-looking statements including but not limited to those with respect to the price of gold, silver or copper, potential mineralization, reserve and resource determination, exploration results, and future plans and objectives of the Company involve known and unknown risks, uncertainties and other factors which may cause the actual results, performance or achievement of Calibre Mining Corp. to be materially different from any future results, performance or achievements expressed or implied by such forward-looking statements. There can be no assurance that such statements will prove to be accurate as actual results and future events could differ materially from those anticipated in such statements. Accordingly, readers should not place undue reliance on forward-looking statements.


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