Fortuna Increases San Jose Ag-Au Resource: Silver Equivalent 17.7 Million Ounces (Indicated), 49.1 Million Ounces (Inferred)
09:01 EDT Monday, March 12, 2007
VANCOUVER, BRITISH COLUMBIA--(CCNMatthews - March 12, 2007) - Fortuna Silver Mines Inc. (TSX VENTURE:FVI) ("Fortuna") is pleased to announce the results of a new resource estimate for the San Jose silver-gold deposit located in Oaxaca, Mexico. San Jose is being explored and developed under a joint venture between Fortuna (76%) and Continuum Resources Ltd. (24%).
Using a cut-off grade of 150 g/t Ag equivalent, the inferred and indicated mineral resources for the Trinidad zone at San Jose are estimated at:
Indicated Mineral Resources: 1.47 million tonnes grading 262.6 g/t Ag + 2.19 g/t Au containing 17.7 million Ag equivalent oz
Inferred Mineral Resources: 3.9 million tonnes grading 260.6 g/t Ag + 2.57 g/t Au containing 49.1 million Ag equivalent oz
A detailed table of the mineral resources for each vein is appended at the end of this release. Also appended is a table showing the sensitivity of the mineral resource to silver equivalent cut-off grade.
Silver equivalency estimates were derived using US$10.30/oz for silver and US$525/oz for gold yielding a Ag:Au ratio of 51:1. Metallurgical recoveries and net smelter returns are assumed to be 100%.
The previous NI 43-101 compliant resources for San Jose were estimated at 527,283 tonnes grading 396 g/t Ag and 3.5 g/t Au (5 g/t Au cutoff), all in the inferred category, for a contained total of approximately 10 million ounces silver equivalent (the NI 43-101 compliant technical report is dated March 2006 and available on SEDAR).
The San Ignacio zone, located approximately 700m along strike to the south of the Trinidad zone, is not included in the current resource estimate. Initial drilling in the San Ignacio area has identified significant silver and gold mineralization but further drilling is required before a meaningful estimate of the resource potential can be made for the area.
Pending receipt of permits, drilling is scheduled to resume at the Trinidad Zone in late March 2007. Initial drilling will be focused on testing the extension of mineralization to depth, and follow-up drilling on the high-grade intercepts at the San Ignacio vein which were reported in 2006 (See news release dated December 7, 2006). Concurrently, surface geochemical and reconnaissance programs will be carried out in the San Jose-Taviche District on concessions recently acquired jointly by Fortuna and Continuum.
Jorge Ganoza, the President of Fortuna, commented: "Fortuna has achieved a new milestone that reflects our commitment to continued growth in shareholder value. San Jose now has nearly five times more silver equivalent ounces in the inferred category than were contained in the previous resource estimate and the system remains open at depth and along strike."
Methodology
The updated resource estimate was prepared by Independent Mining Consultants, Inc. of Tucson, Arizona. Mike Hester acted as the independent qualified person as defined by Canadian National Instrument 43-101.
The estimate is based on all drilling completed to-date and 692 channel samples collected from the underground workings in the Trinidad zone.
The methods used in determining and reporting the resources are consistent with CIM Best Practice Guidelines for the estimation of mineral resources and mineral reserves. For the purposes of the estimate, metal prices were assumed at US$10.30/oz for silver and US$525/oz for gold yielding a Ag:Au ratio of 51:1. Metallurgical recoveries and net smelter returns are assumed to be 100%. A rock density of 2.59 t/m3 has been assumed for both mineralized vein and wall rock materials based on specific gravity measurements taken from 64 vein and wall rock samples.
Three-dimensional wireframe models were developed for each vein system and drill hole grades were composited to 2m intervals. The block model was based on 2m by 2m by 2m blocks. To improve grade estimation, the easting coordinate was replaced by a footwall distance coordinate for both the model blocks and the drill hole composite data. This resulted in straightening of the veins for estimation purposes.
Silver and gold grades in the veins were estimated by inverse distance squared with a search radius of 120m along the strike of the vein, 120m in a dip direction of the vein and 10m in a transversal direction of the vein. Silver composites exceeding 1700 g/t and gold composites exceeding 20 g/t were restricted to search radii of 50m along the local strike of the vein and 50m in the dip direction of the vein. Silver and gold grades were also estimated for stockwork zones by inverse distance squared but with more limited search radii of 30m in a north-south direction, 30m in a vertical direction and 10m in the east-west direction.
For sensitivity analysis and comparison purposes, resource estimates were also prepared using ordinary kriging, nearest neighbor polygon and un-restricted inverse distance methods. Globally, the inverse distance and ordinary kriging methods resulted in similar block grade distributions but the inverse distance did a better job of tracking local grade variations. Resource estimates were validated by comparison of cross sections of the model blocks with drill hole composites.
A full NI 43-101 compliant report will be filed on http://www.sedar.com within 45 days of this news release. The report will be co-authored by M. Hester of Independent Mining Consultants and Gerry Ray, a consulting geologist with extensive experience at the San Jose project and a qualified person (QP) under the definition of NI 43-101. Mr. Hester is responsible for the accuracy of this press release.
Background
Fortuna is a growth-oriented silver and base metal producer focused on mining opportunities in Latin America. The Company's primary assets are the Caylloma Silver-Base Metals Mine in southern Peru and the San Jose Silver-Gold Project in Mexico. The Company is aggressively pursuing additional acquisition opportunities. For more information, please visit our website at http://www.fortunasilver.com.
ON BEHALF OF THE BOARD,
Jorge Ganoza Durant, President
Fortuna Silver Mines Inc.
San Jose Mineral Resource - Cutoff Grade of 150 g/t Silver Equivalent
--------------------------------------------------------------------------
Resource Ag Au Ag Eq
Classification tonnes (g/t) (g/t) Ag (oz) Au (oz) (g/t) Ag Eq (oz)
--------------------------------------------------------------------------
Indicated Mineral
Resources
--------------------------------------------------------------------------
Trinidad Vein 824,000 232.2 1.78 6,151,600 47,200 322.8 8,559,000
--------------------------------------------------------------------------
Bonanza Vein 599,000 310.5 2.80 5,979,800 53,900 453.3 8,729,000
--------------------------------------------------------------------------
Bonanza Splay
Vein 0 0.0 0.00 0.0 0.0 0.0 0
--------------------------------------------------------------------------
Paloma Vein 48,000 185.2 1.54 285,800 2,400 263.8 408,000
--------------------------------------------------------------------------
Total Indicated
Resource 1,471,000 262.6 2.19 12,417,200 103,500 374.0 17,696,000
--------------------------------------------------------------------------
--------------------------------------------------------------------------
Inferred Mineral
Resources
--------------------------------------------------------------------------
Trinidad
Vein 1,687,000 268.0 2.13 14,536,100 115,500 376.7 20,427,000
--------------------------------------------------------------------------
Bonanza Vein 1,609,000 272.6 3.35 14,102,000 173,300 443.6 22,940,000
--------------------------------------------------------------------------
Bonanza Splay
Vein 15,000 694.2 4.48 334,800 2,200 922.5 447,000
--------------------------------------------------------------------------
Paloma Vein 373,000 194.3 1.59 2,330,100 19,100 275.5 3,304,000
--------------------------------------------------------------------------
Stockwork Zone 214,000 196.6 1.67 1,352,700 11,500 281.6 1,939,000
--------------------------------------------------------------------------
Total Inferred
Resource 3,898,000 260.6 2.57 32,655,700 321,500 391.5 49,057,000
--------------------------------------------------------------------------
San Jose Mineral Resource Estimate by Silver Equivalent Cutoff Grade
--------------------------------------------------------------------------
Ag Au Ag Eq
Cutoff Grade tonnes (g/t) (g/t) Ag (oz) Au (oz) (g/t) Ag Eq (oz)
--------------------------------------------------------------------------
130 g/t Ag Eq 5,796,000 249 2.34 46,457,000 435,000 368 68,652,000
--------------------------------------------------------------------------
150 g/t Ag Eq 5,369,000 261 2.46 45,073,000 425,000 387 66,748,000
--------------------------------------------------------------------------
180 g/t Ag Eq 4,614,000 284 2.72 42,178,000 403,000 423 62,741,000
--------------------------------------------------------------------------
200 g/t Ag Eq 4,141,000 302 2.90 40,168,000 386,000 450 59,849,000
--------------------------------------------------------------------------
FOR FURTHER INFORMATION PLEASE CONTACT:
Fortuna Silver Mines Inc.
Jorge Ganoza Durant
President
(604) 484-4085
Website: http://www.fortunasilver.com