Focus Ventures Ltd. (TSX-V: FCV.V) has announced that it has signed an Option and Purchase Agreement to acquire the Santa Rosa Mine, a high-grade Ag-Zn-Pb deposit located 100km north of the Peruvian capital, Lima, and 70km southeast of Focus' Minas Chanca silver project.
The 551 hectare property is situated at an altitude of between 4,000m and 4,500m above sea level within the prolific Central Peru Polymetallic Belt, which hosts a number of world class silver, lead and zinc deposits such as Iscay Cruz, Uchucchagua and Cerro de Pasco. The Santa Rosa project represents the Company's fourth acquisition in its on-going search for high-potential, advanced-stage projects across Peru. Focus is currently drilling its Chúcara gold-silver project, located in the La Libertad mining district.
Focus' geologists collected a total of 139 chip channel samples from surface and underground workings over various mineralized zones within the property consisting of vein, stockwork and breccia mineralization. Sampling highlights include:
The average grade of silver was 7.6 oz/t, with values from trace to 107.4 oz/t (median value 2.1 oz/t). Lead and zinc averaged 5.5% and 7.3% respectively, with lead values ranging from trace to 28% (median value 1.9%) and zinc grades ranging from trace to 36.6% (median value 5.2%). Average sample width of the 139 samples was 1.03m, ranging from 0.2 to 3.5m.
Geology and Mineralization
Mineralization at Santa Rosa is hosted by Cretaceous-age quartzites, sandstones, shales and limestones pertaining to the Chimu and Santa Formations, and Tertiary volcanic rocks of the Calipuy Formation. The rocks have undergone several episodes of faulting and associated precious and base metal mineralization.
The Santa Rosa and Milagros-Sally zones are exposed in underground workings over 2 levels as broad zones of stockwork, massive sulphide and breccia-hosted Mineralization emplaced within steeply dipping and brecciated quartzites and shales that exhibit a strong structural control. The zones are interpreted as chimneys or pipes developed along the intersection of several faults. Multi-directional stockwork mineralization forms broad northeast trending zones with preferential dips to the southeast and northwest.
The Milagros-Sally mineralized zone is located approximately 100m to the south of Santa Rosa, and consists of galena and sphalerite stockwork veining over two levels, with broad channel sample intercepts of up to 4m. The property underwent some small scale production in 2008, when 2,233t of ore grading 6 oz/t Ag, 8.75% Zn and 6.6% Pb was mined exclusively from the Santa Rosa and Milagros zones.
Although the Santa Rosa and Milagros-Sally mineralization does not manifest in outcrop, surface rocks are characterized by strong manganese and hematitic alteration that could indicate a high level "cap" to the sulphide stockworks and veins observed in underground workings. Zones of surface alteration and anomalous geochemistry have been traced along trend of the Santa Rosa and Milagros-Sally zones, and similar alteration has been identified in other areas of the property, including Santa Rosa Sur located 450m south of Santa Rosa, and Zona Oxidos located 430m northwest of Santa Rosa. Five surface samples taken from Santa Rosa Sur assayed strongly anomalous in Mn, Pb and Zn. At Zona Oxidos highly anomalous Mn was received with up to 1% combined Pb and Zn in surface samples. These areas represent additional high priority targets for geophysics and drilling.
(ii) Epithermal Ag-Pb-Zn Veins
At least 6 intermediate sulphidation veins have been mapped to date on the property including the Yanapata, Macayaca, Lourdes, Esperanza, Huayllay and Shalka veins, three of which have been traced over 1km in strike by mapping. The Yanapata vein is the only structure that was exploited historically by underground methods. Bonanza Ag grades include 0.7m @ 107.4 oz/t Ag, 11.7% Pb and 11.8% Zn. Vein widths sampled average 1.0m ranging up to 3.5m. Surface sampling geochemistry on the other veins indicates potential for similar grades at depth.
Target and Planned Exploration
Focus is targeting a high grade Ag-Pb-Zn deposit at similar grades to those mined historically. A PIMA alteration study undertaken by Focus highlighted predominantly illite and kaolinite alteration, confirming the high level and relatively un-eroded hydrothermal system at Santa Rosa. The property has never undergone any systematic modern exploration such as geophysics and is presently undrilled. Work planned by Focus will consist of a high density, high -resolution CSAMT survey to map the subsurface signature of known mineralization and prove up additional targets, followed by drilling. Work is subject to the granting of the usual permissions.
Under the terms of an agreement signed with the property owner, a local Peruvian company, Focus can earn 100% in the property by making cash payments totalling US$9 million over 4 years, including US$100,000 on signing (paid) and a series of incremental payments including US$2,500,000 and US$5,000,000 on the third and fourth anniversaries respectively. For future resources defined in Measured and Indicated categories in excess of 5 million tonnes, a royalty of US$1.19 per tonne will be payable.
The scientific and technical information in this release was prepared under the supervision of Mr. David Cass, Focus's President, who is a member of the Association of Professional Engineers and Geoscientists of British Columbia, and a "Qualified Person" in accordance with NI 43-101.
Samples were analyzed by ALS Chemex Laboratories in Lima. Gold was assayed by Atomic Adsorption Spectrometry with fire assay gravimetric finish. Silver was determined by multi-acid digestion and ICP-AES, with AA finish. Lead and Zinc were determined by ICP with Atomic Adsorption Spectrometry and volumetric finish. ALS Chemex's quality control system complies with International Standards ISO 9001:2000 and ISO 17025:2005. Analytical accuracy and precision are monitored by the analysis of reagent blanks, reference material and replicate samples. Focus' own blanks and duplicates were included in the sample stream.
Source: Focus Ventures Ltd.