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The Salamanca I Project covers an area of 280,320 ha and includes several other untested areas of uranium mineralization and radiometric anomalies. The Retortillo and Santidad deposits are only a few kilometers apart within the same stratigraphic horizon. Zona 7 is located 14 kilometres to the north.
Berkeley commenced drilling at Retortillo in December 2006. Since then, the Company has calculated JORC compliant inferred and indicated resources totaling 16.9m lb of U3O8 as detailed below: At a 200ppm U3O8 cutoff, total inferred and indicated resources are:
including the following indicated resources:
Full details of the latest resource estimate are available in the Company’s ASX Announcement dated 19 November 2007. In February 2008, Berkeley released the results of a Scoping Study on mining at the Salamanca I project. The study was prepared by AMC Consultants and confirmed the potential economic viability of the Project. The Study, which was based only upon the project’s previously announced JORC inferred and indicated resources of 16.9m lb of U3O8 included the following outcomes:
Further details of the Scoping Study are available in the Company’s ASX Announcement dated 14 February 2008. In late 2007, Berkeley conducted a helicopter airborne radiometric and magnetic survey over the Salamanca I project. The survey comprised 3,336 line kilometers flown by an internationally recognized contractor on 100m spaced north-south lines using a towed magnetic sensor at a nominal height of 35m with a spectrometer inside the aircraft. The survey confirmed and extended the potential to add additional uranium resources in outcropping and covered areas in proximity to the existing resources. In particular, it has significantly enlarged target areas associated with known uranium mineralization at the Zona 7 deposit, and at two previously mined areas, Mina Caridad and Mina Cristina. It has also identified covered extensions of favourable lithology along strike from the Retortillo and Santidad deposits.
Further details of the Aerial Survey can be found in the Company’s ASX Announcement dated 5 February 2008. Berkeley is undertaking a vigorous new program of RC drilling with the aim of assessing the highest priority targets. Project Geology Uranium was first located in this area by the JEN in the late 1950s. Their exploration activity continued until 1974, when their interests were ceded to ENUSA. In the meantime, JEN had located the 'Caridad' and Cristina deposits and a series of other anomalous zones. The area consists of open rolling hills, incised by small valleys and meandering drainages. It is subject to mixed cultivation, orchards and grazing country with farms and scattered villages. Outcrop is very good in the majority of the project areas, particularly in the central and northwestern portions. Residual, skeletal soils generally occur between depths of 0.1 to 3.0 metres over saprock and fresh bedrock in most places. The depth of weathering in the project area varies up to 25 to 35 metres depth. The host rocks of Retortillo-Santidad uranium mineralisation in the Salamanca I project area chiefly comprises sequences of Ordovician -aged siltstones, phyllites and quartzite lenses in an anti-formal zone which is thrust over earlier Precambrian chlorite-sericite schists, slates, quartzites and conglomerates. These Precambrian aged metasediments are the host rocks for the Caridad, Villares and other uranium occurrences in the central and northern parts of the project area. Ordovician aged metasediments are preserved in the southern parts of the project. These rocks exhibit basal quartzites overlain by pyritic carbonaceous shales, the later of which are the host rocks for the Retortillo Prospect. The early Palaeozoic stratigraphy strikes WNW and is recumbently and isoclinally folded. The metamorphic grade is greenschist facies. The metasediments are intruded by the WNW trending Hercynian aged Banobarez Granodiorite in the southern part of the project area, which in turn is cross cut by the later Hercynian aged Villavieja - Ciperez Granite to the west. The style of the primary uranium mineralisation in the Salamanca area is one of brittle deformation associated with vein, stockwork, and disseminated alteration in joint / fracture filling. Textures exhibited include veining and disseminated fracture filling accompanied by silicification (vein quartz and chalcedony), sericite and carbonate, pyrite +/- marcasite alteration. The recognised primary uranium minerals are pitchblende and coffinite with much of the mineralisation in the schistosity. The primary mineralisation appears to be controlled by interplay of NW and NE striking structural zones, concurrent with favourable stratigraphic units of pyritic carbonaceous shales. Studies of the mineralisation from the Fe Mine, to the southwest of the Salamanca I project area, indicate that the age of the uranium mineralisation in this region of Spain is between 35-57Ma, corresponding with the Lower to Mid Tertiary, Alpine Orogeny. The uranium mineralised faults and shears are probably associated with lower Tertiary aged wrench faulting. Secondary uranium mineralisation appears to be developed in "supergene-like" tabular zones of mineralisation developed near surface and down to around a maximum depth of 20 to 50 metres vertical depth, corresponding with the local depth of oxidation. Location of mineralisation relative to the redox front is not clear at this stage. It is considered that, at least in part, the uranium mineralisation may be a hybrid “unconformity” style, developing on or near the now largely eroded Tertiary unconformity. The secondary mineralisation in the Salamanca area consists of fine fracture and joint coatings and discrete crystals of gummite, alpha-uranitite, phosphor-uranium minerals, autunite and torbernite. The Tertiary aged sedimentary cover of the Duero Basin covers the southeastern portions of the project area. These young sediments consist of weakly consolidated conglomerates, arkose and carbonate cemented sandstones. As far as can be ascertained at this stage, the depth of this Tertiary cover in this area does not exceed 10 to 50 metres depth for 1 to 4 kilometres south and southeast of Retortillo. Historic exploration at Retortillo has demonstrated that even thin (less than 1 to 2 metres) Tertiary or Recent aged sedimentary cover sequences will suppress all surface radiometric responses from any underlying radiometric source.
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