Uranium and copper mineralization, accompanied by highly anomalous radioactivity, are widespread on the Siviez property. The occurrences of mineralization straddle the contact between the Siviez metavolcanic rocks and Nendaz metasedimentary rocks, along a distance of approximately 6 km that extends almost the full length of the Siviez Exploration Permit, interrupted in a few areas by scree cover. Uranium mineralization, at a depth of 800 m below surface and within the same geological horizon that hosts the surface occurrences, was identified in 1957 during hydroelectric tunnelling and is indicative of the potential for large scale deposits.
Historic work has reported values of up to 504,000 ppm U (59.43% U3O8) and 285,000 ppm U (33.6% U3O8), as well as local gold enrichment (up to 11.9 g Au/t). Four main mineralized areas have been the focus of exploration sporadically from 1957 through to 1993, and by the Company since 2007. Notwithstanding intermittent work over a period of several decades, only one exploration drill hole was ever attempted. The key areas along the 6 km trend include, from north to south, Grand Alou (and Plan du Fou), Le Fou, Les Plans, and Col des Mines.
At Grand Alou, uranium, copper (and in places silver, gold) mineralization outcrops over an area of about 200 m x 200 m in metamorphosed channel-fill conglomerates and sandstones of the Nendaz Series. The Company’s exploration program in 2009, resulted in 45 samples containing >0.1% U3O8, of which 21 contained >0.5% U3O8. Of the same 45 samples, 22 contained >0.5% Cu. At Plan du Fou, of a total of 39 samples, 12 contained >0.1% U3O8.
Le Fou has the largest concentration of radiometric anomalies, occurring over an area of approximately 700 m x 350 m on the northwestern mountain face. Significantly, there is about 1,000 m of elevation separating the mineralization at the summit of Le Fou from the mineralization identified in the Fionnay-Nendaz water tunnel directly below Le Fou, where, in 1957, three large-volume samples yielded 0.03% U (0.035% U3O8) to 0.15% U (0.177% U3O8). Sampling in the easily accessible lower areas of Le Fou by the Company resulted in six of 52 grab and channel samples returning analyses of >0.1% U3O8, including a grab sample with 0.87% U3O8and 0.01% Cu, and a channel sample containing 2.48% U3O8 and 0.72% Cu across 0.72m.
At Les Plans, outcrop exposure is limited. In this area, in 1984, the only drill hole attempted on the Siviez Project intersected a significant radioactive interval, but did not reach the target due to technical problems. During the Company’s 2009 program, of 4 samples taken, three contained >0.1% U3O8 including 0.32% U3O8, 0.68% Cu and 16.1 ppm Ag.
At Col des Mines, located roughly 6 km south-southwest of Grand Alou, pitchblende-pyrite-chalcopyrite mineralization occurs within the Nendaz metasedimentary rocks. An adit, excavated in 1968, followed mineralization for 163 m, with a zone at surface traced for almost 600 m. Of the 21 samples collected by the Company in 2007 and 2009, 10 contained >0.1% U3O8 (up to 3.1% U3O8) and up to 2.50% Cu. The best channel sample contained 0.11% U3O8 and 0.86% Cu across 0.64 m.
Uranium mineralization at Siviez consists of pitchblende and coffinite occurring as disseminations, pods, and swarms of small veins, with pyrite and ubiquitous copper sulphides (chalcopyrite, tetrahedrite, chalcocite, covellite), as well as secondary copper carbonates (azurite and malachite). Native gold has been identified, but its distribution is as yet unclear.
Description, Location, and Access
Aurania holds a 100% interest in the Siviez uranium-copper-silver-gold Property, through a wholly-owned subsidiary, AuroVallis Sarl. The property consists of a single 31.6 km2 Permis de Fouilles (“Permit”) located about 20 km southwest of Sion, which is about 160 km east of Geneva along the Rhône River valley.
Road access and infrastructure in the surrounding areas is excellent, with the Rhône River valley corridor within 10 km of the Property. The Permit area is mostly uninhabited, although there are a few towns nearby. The topography varies from gentle to steep, with vertical relief of approximately 1,485 m. Loose surface roads provide access into many parts of the Permit area.
Uranium was first discovered at Siviez in 1957, when radioactive anomalies and pitchblende mineralization were encountered 800 m below surface (1,400 m ASL) during construction of a water conduit tunnel that extends under the Property. Bulk samples weighing 6-t and 3.6 t, containing 0.177% and 0.083% U3O8, respectively, were extracted from two higher-grade areas. This mineralization was traced up-dip to surface at 2,200-2,400 m asl where anomalous uranium mineralization was identified and traced along a 5 km strike
A Swiss utility company held an exploration permit over the ground from 1959 through to 1993. The mineralized areas at surface including Grand Alou, Le Fou, Les Plans and Col des Mines were first discovered in 1958-59. At Grand Alou, a number of trenches were excavated in mineralized locations containing an abundance of malachite, a secondary copper mineral. At Le Fou, numerous small trenches were dug and sampled. In 1968, a 160 m long adit was excavated at Col des Mines to follow a series of subparallel zones of uranium-copper mineralization. From 1982 to 1984, a Swiss government agency continued exploration,
consisting of trenching of the various occurrences at Le Fou, Grand Alou and Les Plans. Some high-grade uranium results were obtained, including up to 504,000 ppm (59.43% U3O8) and 285,000 ppm U (33.6% U3O8), as well as local gold enrichment (up to 11.9 g Au/t near Grand Alou). In 1984, a single diamond drill hole was attempted at Les Plans, but was abandoned short of the target due of technical difficulties. In 1993, strong radiometric anomalies were detected in a new water conduit tunnel beneath Grand Alou, at 2,157 m asl, or about 240 m below surface.
In 2007, Aurania commissioned a helicopter-borne radiometric and magnetic survey, covering a 7 km strike length over the known uranium occurrences. The survey identified a trend of radiometric anomalies extending virtually the full length of the survey and closely correlating with the contact between the Siviez metavolcanics and Nandez metasediments.
In 2009 and 2010, Aurania completed a full compilation of historic information and conducted ground geological programs including surface sampling. Historic occurrences were located and sampled, airborne
radiometric anomalies were investigated, and a number of new uranium occurrences were located. By the end of the 2010 field season, first phase drill targets were identified and drilling permits were obtained. Aurania commissioned a baseline water survey over the Siviez permit area that was completed by Bureau d’Etudes Géologiques SA in late 2010.
A National Instrument 43-101 compliant report was completed by Watts, Griffis and McOuat Limited, dated October 15, 2010.
Urania has identified drill targets in five main areas along the 6 km strike length of anomalies. Drilling will be a key part of the exploration program for 2011.
Proposed Work Programs and Budgets
The Companies proposed Phase 1 exploration program for 2011 includes an initial 2,500 meter diamond drilling program to drill test, for the first time since its discovery in the late 1950s, the uranium-copper mineralization along the contact between the metasediments and metavolcanics. Additional work will include: preparation of a 3-D model of all data to assist in the layout of diamond drilling; additional prospecting, mapping and sampling, as warranted; a pilot radon-in-soil survey to test its effectiveness over areas where the metasediment metavolcanic contact is obscured and, if effective, an expanded survey. A Phase 1 budget of $2,200,000, including a 10% contingency allowance, is proposed.
A Phase 2 program of 3,000 m of diamond drilling is proposed to test the wide area of anomalies at Le Fou with additional drilling at Grand Alou, Plan du Fou and Col des Mines, being to some degree contingent on the success of Phase 1. The proposed Phase 2 budget of $2,400,000 includes a 10% contingency allowance.
Download the NI 43-101 technical report for Aurania’s Siviez project in Switzerland.