BKY Berkeley Energia Limited

RNS Number:5732U
Berkeley Resources Limited
10 April 2007



10 April 2007


INITIAL JORC COMPLIANT RESOURCE OF 11.9 MILLION POUNDS OF U3O8 AT SALAMANCA 1
PROJECT


The Directors of Berkeley Resources Limited ("Berkeley" or the "Company") (AIM:
BKY.L) are pleased to announce that the Company has completed an initial JORC
compliant resource estimate for the Retortillo and Zona 7 uranium deposits
totalling 11.9 million pounds of U3O8, at an average grade of  723ppm. There are
additional smaller deposits in the Salamanca 1 area not included in this
estimate.


This estimate is based on data from historical drilling campaigns by the Junta
de Energia Nuclear (JEN) and Empresa Nacional Uranio S.A. (ENUSA) in the period
from the late 1950's to the mid 1980's. Historical data has been verified and
re-interpreted with the aid of an eighteen hole diamond drilling programme
recently completed by Berkeley. Resource estimates have been developed by a team
of in-house and consulting geoscientists with calculations based on block
modelling methods (for Retortillo) and the polygonal method (for Zona 7).


The Retortillo deposit is approximately 30 kilometres northeast of the former
ENUSA mining operation of Mina Fe at Ciudad Rodrigo and about 65 kilometres
southwest of the provincial capital of Salamanca. Primary (pitchblende and
coffinite) and secondary (uraninite and torbernite) uranium is hosted in
andalusite-rich, biotite-altered Ordovician metasediments (phyllites) which have
been hydrothermally altered to sericite +/- pyrite. At the Zona 7 deposit,
approximately 14 kilometres to the north, shallow secondary uranium is hosted by
poorly outcropping, biotite-altered Late Precambrian - Early Cambrian phyllites.


Retortillo and Zona 7 were discovered by JEN during regional prospecting
programs in the 1950's and explored by geophysical methods and drilling. A total
of 272 diamond and percussion holes at Retortillo, and 71 at Zona 7 were drilled
by JEN and ENUSA through to the 1980's. At Retortillo, drilling defined two main
zones of uranium mineralisation, but did not test the extension of the
radiometric anomaly to the northwest, nor close off the mineralisation to the
southeast. This mineralisation outcrops in several areas, but is usually covered
(preserved) by a shallow layer of unconsolidated Tertiary sands, clays and
gravels, that thickens to the southeast. It has been intersected at depths of up
to 77m. Petrological, mineralogical and metallurgical studies are currently
being undertaken on samples of oxidised and primary mineralisation.



At Zona 7, two areas of continuous mineralisation have been defined within an
arcuate, 1200 x 200m east-west anomaly. Other mineralised areas within the
anomaly have been excluded until further drilling is undertaken to resolve some
inconsistencies in the historical data. Most of the uranium mineralisation is
believed to be secondary and occurs within 20m of the surface. The Zona 7
anomaly appears to be open and untested to the west and north.



This initial resource estimate is an important milestone in the evolution of the
Company. A programme to test the southeast extension of the Retortillo deposit
has commenced, and will be followed by drilling of the untested radiometric
anomaly to the northwest of the deposit. This work, together with testing of
other targets within the Salamanca I licence (such as Zona 7) will be aimed at
assessing global resource potential for the project. In addition a small number
of targeted angle holes within the Retortillo deposit aimed at resolving
uncertainties in the current interpretation, is expected to allow
reclassification of much of the resource to the "Indicated" category.




Background



The Salamanca I Project covers 16,912ha and contains several known uranium
occurrences, including the Retortillo and Zona 7 deposits.



The Junta de Energia Nuclear (JEN) and Empresa Nacional Uranio S.A. (ENUSA)
conducted regional and project scale investigations from the late 1950's to the
1980's and identified several areas of uranium mineralisation and anomalous
radiometrics within the Salamanca I project area. These include the Retortillo,
Zona 7, Caridad, Cristina, Zona 35 and Zona 19 occurrences. The Retortillo and
Zona 7 uranium deposits were selected for further evaluation on the basis of
size, grade, and depth of mineralisation and completeness of historical data.



Recovery, reformatting, compilation and interpretation of the extensive array of
historical data over the last 12 months has been supplemented by the recent
drilling programme along selected traverses at Retortillo and check drilling at
Zona 7. This work has enabled resource estimates for these deposits and also
highlighted other prospects within the Salamanca I project area.



Mineralogical, petrological and metallurgical testwork on oxidized and primary
mineralisation from the Retortillo deposit is in progress.



Resource Estimation



Resource estimates for the Retortillo and Zona 7 uranium deposits have been
carried out by a team of in-house and consulting geoscientists. Assessment and
interpretation of the historical and recent drilling data was undertaken by
Company geologists; assessment of radiometrics and calculation of radiometric
equivalent assays were completed by Roger Murphy (former Chief Geologist of the
Rossing uranium mine); and resource modelling was assisted by McDonald Speijers
(a consulting group with 15 years' experience in resource estimations). The
resource for the Retortillo deposit was calculated using block modelling
methods, while the Zona 7 resource was estimated using a plan polygonal method.
Resource classification has been carried out in accordance with the JORC Code.


                Ore Tonnes (Mt)    Grade (ppm U3O8)     Contained (Mlb U3O8) at 
                                                          200ppm U3O8 cutoff
Retortillo       6.80                720                       10.8
Zona 7           0.62                760                        1.1
TOTAL            7.42                723                       11.9



Note - for comparative purposes - previously published resource targets at
Salamanca 1 (based on historic ENUSA estimates) included an additional 590,000
pounds of U3O8 in 3 small deposits, upon which Berkeley has done no work and
which are therefore not included in the above calculations.



Grade was estimated using a calculated U3O8 value. Most historic assays were
fluorometric analyses, which were used in preference to the few spectrometric
analyses. Where no chemical analyses were available, radiometric equivalent
assays were determined from downhole radiometric surveys using comparisons
between available radiometric and chemical data sets.



The block model employed block sizes of 12.5m x 12.5m x 2.5m within a wireframe
defined by interpretation of the geological and radiometric data. A universal
specific gravity of 2.5 was used for the conversion of volume to tonnes, based
on in-house measurements. The same measure was used by ENUSA in the previous
resource estimates. A top cut of 4,000ppm was also applied.



When ENUSA commenced exploration of the Salamanca area in the late 1970's and
early 1980's it checked the earlier JEN drill core and samples by re-logging,
re-sampling and re-analysing the core and/or JEN sample pulps, and by
radiometrically re-logging remnant JEN core. Although no useable drill core or
samples now exist from the JEN and ENUSA drilling, the recent diamond core
drilling by Berkeley has provided a check on both the JEN and ENUSA (diamond and
percussion) drilling. Recent drill results at least equal, or exceed, the
historical drilling in both grade and intersected widths. The recent holes were
radiometrically logged, and subjected to geological logging, sampling and
assaying over the entire core length. Core recoveries were in excess of 93%.



The close spacing of historical drilling over most of the Retortillo deposit,
and the amount of resulting assay and radiometric data, is sufficient to
consider upgrading the resource category to "Indicated" for most of the
Retortillo resource. However, 3D modelling of the deposit reveals some
inconsistencies in the interpretation which require resolution by selected angle
holes, prior to any reclassification of Retortillo resources.



Retortillo Deposit



Initial JEN drilling at the northwestern end of the deposit was on a 50 x 50m
grid. After some check/infill drilling at grid centres, ENUSA continued drilling
the southeastern part of the deposit on a 50 x 50m grid. Later drilling to the
southeast and along the deposit margins was on a 100 x 100m grid with final
stage step-out drilling at 200m centres in the far southeast of the deposit. The
Berkeley check drilling was on 50m centres along grid lines 22E, 61E and 93E.



The Retortillo deposit is hosted in andalusite-rich, biotite-spotted schists and
appears to be fault-bounded to the northeast and southwest. Chlorite-spotted
schists are not known to host any significant mineralisation apart from a thin
secondary horizon. The top of the mineralisation is associated with the upper
appearance of sulphides and is generally sharp, horizontal and within 24m of the
surface. The base of mineralisation is irregular and can be associated with the
base of partial weathering. Parts of the mineralisation are overlain by a thin,
protective Tertiary cover, which appears to preserve the secondary enrichment
zones. Mineralisation is associated with hydrothermal sericite, pyrite +/-
chlorite alteration and averages 15.5m in thickness. The primary mineralisation
consists of pitchblende, coffinite and black oxides incorporated into the main
steeply dipping schistocity. A secondary enrichment of dominantly autunite and
torbernite occurs as a sub-horizontal layer.



The deposit consists of two main blocks separated by the Retortillo Creek. The
northwestern block lacks Tertiary cover and the mineralisation has been affected
by weathering and erosion. Although the northern part of the southeastern block
has been similarly affected by weathering, due to the lack of Tertiary cover,
from grid line 60E the Tertiary cover increases to a maximum of around 30m in
the southeastern parts of the deposit. Secondary mineralisation is better
developed beneath this Tertiary cover.



An Inferred Resource of 6.8Mt at a grade of 720ppm U3O8 with 10.8Mlbs of
contained U3O8 has been estimated using a 200ppm U3O8 lower cut-off.



Zona 7 Deposit



The Zona 7 deposit is 14 kilometres to the north of Retortillo. It occurs within
an arcuate east-west trending radiometric anomaly measuring some 1,100m x 200m.
JEN tested the anomalous areas on an incomplete 50 x 50m grid, with more intense
drilling within an area of about 400m x 200m which includes the estimated
resource.



Significant mineralisation occurs at very shallow depth ( < 20m) as a
near-surface, flat lying layer which tends to dip more steeply to the northeast
in the northwestern zone. The discontinuous mineralisation is dominantly
gummites and black oxides with significant torbernite and autunite occurring in
thermally altered biotite + chlorite spotted schists. The deposit is generally 5
to 15m thick, with some intersections in excess of 30m in the northern parts.



Significant inconsistencies within the JEN drill data for the eastern half of
the radiometric anomaly have precluded inclusion of these results in the
resource estimate. It is anticipated that these inconsistencies will be resolved
by a short programme of targeted drilling.



Resources for the Zona 7 Deposit were estimated using a plan polygonal method
based on a deposit shape defined by geological, geochemical and radiometric
data. A specific gravity of 2.5 was used for conversion of volume to tonnes
(used historically by ENUSA).



An Inferred resource of 625,000t at a grade of 760ppm U3O8 with 1.1Mlbs of
contained U3O8 has been estimated using a 200ppm U3O8 lower cut-off.



Ongoing Work



Further infill and extension drilling is in progress at Retortillo to confirm
and clarify the current resource model, upgrade the resource category and to
determine the southeast extent of the deposit. Additional drilling is planned to
test for an extension of the deposit across the Rio Yeltes to the northwest,
where a 2km long ground radiometric anomaly equal in strength to the Retortillo
anomaly, has never been tested.



Further ground radiometrics and drilling will also be undertaken at Zona 7 in
order to extend this resource, and other known anomalies will also be
investigated with the aim of determining total resource potential within the
Salamanca 1 project area.



Glossary


Autunite:                    Hydrous phosphate of uranium and calcium occurring as a secondary mineral.
Andalusite:                  A natural alumino-silicate mineral.
Arcuate:                     Curved or bowed.
Biotite:                     A mineral of the mica group, widely distributed in a variety of rocks.
Cambrian:                    A geological time period from 544 to 494 million years ago.
Coffinite:                   A uranium silicate mineral.
Chlorite:                    A platy hydrous silicate related to mica.
Fluorometric:                A measure of the intensity of fluorescence.
Gummites:                    A mixture of yellow or orange secondary uranium oxides formed by alteration
                             of uraninite.
Hydrothermal:                Of or pertaining to heated water, to its actions or to products related to
                             its actions.
JORC, JORC Code:              Joint Ore Reserves Committee, common reference to the Australasian Code
                             for Reporting of Exploration Results, Mineral Resources and Ore Reserves,
                             2004.
Metasedimentary:             General term used to describe sedimentary rocks which have been
                             metamorphosed.
Ordovician:                  A geological time period from 505 to 440 million years ago.
Phyllite:                    A cleaved metamorphic rock with affinities with both slates and schists.
Pitchblende:                 Also called Uraninite. Uranium oxide mineral.
Radiometric:                 Measurement of radioactivity useful in mapping rock formation.
Sedimentary:                 Rocks formed of particles deposited from suspension in water, wind or ice.
Sericite:                    A fine grained version of muscovite mica
Spectrometric:               A measure of the wavelengths at which absorption bands occur in an
                             absorption spectrum.
Tertiary:                    The first period of the Cenozoic era (after the Mesozoic era and before the
                             Quaternary period), spanning the time between 65 and 1.8 million years ago.
Torbernite:                  Hydrated copper uranium phosphate mineral.
Uraninite:                   An isometric uranium mineral, UO2, that is highly radioactive and the
                             primary ore of uranium. Usually occurs in granular masses or aggregates.



The technical content of  this report has been reviewed and approved  by Mr
Peter Ellis, a Member of The Australian Institute of Geoscientists and an
employee of Berkeley Resources Limited. Mr Ellis has sufficient experience which
is relevant to the style of mineralisation and type of deposit under
consideration and to the activity which he is undertaking to qualify as a
Competent Person as defined in the 2004 Edition of the 'Australasian Code for
Reporting of Exploration Results, Mineral Resources and Ore Reserves'. Mr Ellis
consents to the inclusion in the report of the matters based on his information
in the form and context in which it appears.









Enquiries -  Managing Director: Matt Syme   Telephone: +61 417 906 717
                                            Email: info@berkeleyresources.com.au


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