Berkeley Eng Regulatory News (BKY)

28 Feb 2007 07:01

Berkeley Resources Limited28 February 2007 BERKELEY RESOURCES LIMITED 28 February 2007 Further drilling results confirm retortillo URANIUM mineralisation The Directors of Berkeley Resources Limited (AIM: BKY.L) are pleased to advisethe results of the next four holes of its confirmatory drilling programme at theRetortillo project in Salamanca Province, Spain. Vertical diamond core hole RTO-002 is located some 100m south easterly along thestrike of the mineralisation from the initial hole RTO-001 (see website:www.berkeleyresources.com.au). Vertical diamond core hole RTO-004 is located afurther 700m south easterly along strike. These holes were designed to test the continuity and tenor of the uraniummineralisation and confirm the results of previous drilling which tested thearea with 50m x 50m and 100m x 100m grids at least 20 years ago. As theRetortillo mineralisation had been tested by different organisations atdifferent times, the current drilling programme is also checking for variationsin the historical results. Chemical assay results for these holes include the following intersections, at a0.02% U3O8 cut-off: Hole RTO-002 13.5 metres @ 0.0307% U3O8 from 26.0m 1.8 metres @ 0.0635% U3O8 from 45.2m Hole RTO-004 4.0 metres @ 0.207% U3O8 from 23.0m 8.3 metres @ 0.0706% U3O8 from 33.7m These results continue to be encouraging for the validation of the previousdiamond and RC drilling and confirm the continuity and predictability of theRetortillo mineralisation. Vertical diamond core holes RTO-003 and RTO-005 were drilled within the northwestern block of mineralisation defined by past work. This block is separatedfrom the main Retortillo mineralisation by a topographically lower zone fromwhich the mineralisation may have been eroded (there is currently no knownmineralisation in this area). There appear to be some differences in the tenorof the mineralisation between the two blocks, with the NW block containing lesshigher grade mineralisation in both the historical and new data. Chemical assays are pending on holes RTO-003 and RTO-005 however, radiometricequivalent assay results include the following intersections at a 0.02% U3O8cut-off: RTO-003 10.0 metres @ 0.0513% U3O8 from 11.5m 8.0 metres @ 0.0507% U3O8 from 28.0m RTO-005 14.0 metres @ 0.0369% U3O8 from 23.0m These results are an encouraging start to the validation of the previous diamondand RC drilling of the NW block of the Retortillo deposit. The correlations between the radiometric equivalent and assay uranium contentsfor holes RTO-001-RTO-002 and RTO-004 are excellent, giving a high level ofconfidence in the assay equivalent estimates for RTO-003 and RTO-005. EFFECT OF APPLYING A 0.01% U3O8 CUTOFF Given current prices for U308, and the prospect of substantial thicknesses ofcontinuous, shallow, oxidised, flat lying uranium mineralisation, theforthcoming calculation of JORC compliant resources for Retortillo will considerlower cut-offs, in addition to the standard 200ppm applied previously. Using a0.01% U3O8 cut-off the intersections become: RTO-002 30.0 metres @ 0.0253% U3O8 from 26.0m RTO-003 30.5 metres @ 0.0357% U3O8 from 11.5m RTO-004 18.0 metres @ 0.0832% U3O8 from 23.0m RTO-005 8.0 metres @ 0.0185% U3O8 from 8.7m; and 19.0 metres @ 0.0312% U3O8 from 23.0m For comparison, application of a 0.01% U3O8 cut-off to the previously announcedresults of RTO-001 gives intersections of: 32.0m @ 0.106% U3O8 from 9.8m 28.2m @ 0.167% U3O8 from 45.8m Hole details include: HOLE_ID DRILLED_BY UTM_E (m) UTM_N (m) RL Inclination EOHRTO-001 INSERSA 719315 4520537 743 -90 97.00RTO-002 INSERSA 719402 4520455 745 -90 91.70RTO-003 INSITU 718603 4521085 738 -90 98.20RTO-004 INSERSA 719969 4520074 738 -90 98.10RTO-005 INSITU 718565 4521180 738 -90 97.15 The Grid has a datum of UTM 29N ED50 The holes were geologically and radiometrically logged before being sampled (1/4core) at approximately 1m intervals (intervals varying from 0.5 to 1.5m based ongeology) for most of the hole length. Tertiary gravels were not sampled.Duplicate 1/4 core samples and blank samples were included. The samples wereassayed for total uranium by the Delayed Neutron Count (DNC) method atActivation Laboratories Limited in Ontario, Canada. The radiometric equivalent assays for holes RTO-003 and RTO-005 were calculatedbased on a comparison of the results of RTO-001 chemical assay and radiometricdata by Roger Murphy (the former Chief Geologist of the Rossing uranium mine). Measured recoveries were good and averaged 93%. Most of the small amount of coreloss was in the Tertiary cover sequence. The geology of the holes currently being assayed is basically similar to thatpreviously reported for hole RTO-001. The drilling confirms the Tertiary coverdips gently to the SE, forming a "planar-based" wedge of sands and gravelson-lapping the eroded shale - greywacke meta-sedimentary terrain. Themineralisation is hosted in chiastolite spotted shales which have been shearedand partially weathered. Most of the visible mineralisation appears to be secondary torbernite, autuniteand pitchblende. The top of the mineralisation is sharp and strong and appearsto be related to the base of total oxidation - uppermost appearance ofsulphides. The upper section of mineralisation is a sub-horizontal zone ofsecondary enrichment. Several lower intersections appear to of a more primarynature. An evolving model for the Retortillo deposit suggests the main higher grade zoneof mineralisation at relatively shallow depth is a result of supergeneenrichment during the long period of peneplanation and enhanced by recentweathering and the current water table. The primary mineralisation may have alithological control with the entire deposit being intimately associated with astrong structural overprint. There are currently 2 diamond drill rigs operating at Retortillo. The currentdrilling programme, together with the interpretation of assay and radiometricdata for the 272 holes drilled previously, is aimed at enabling calculation of aJORC compliant resource. The technical content of this report has been reviewed and approved by MrPeter Ellis, a Member of The Australian Institute of Mining and Metallurgy andan employee of Berkeley Resources Limited. Mr Ellis has sufficient experiencewhich is relevant to the style of mineralisation and type of deposit underconsideration and to the activity which he is undertaking to qualify as aCompetent Person as defined in the 2004 Edition of the 'Australasian Code forReporting of Exploration Results, Mineral Resources and Ore Reserves'. Mr Ellisconsents to the inclusion in the report of the matters based on his informationin the form and context in which it appears. Enquiries -Matt Syme Telephone: +61 417 906 717 Managing Director Facsimile: +61 8 9322 6558 Email: info@berkeleyresources.com.au This information is provided by RNS The company news service from the London Stock Exchange