RNS Number:2728O
Monterrico Metals PLC
04 August 2003

Initial Resource Estimate at Rio Blanco Copper project in Peru





London, 04 August 2003 :    Monterrico Metals plc ("Monterrico") is pleased to
announce that an independent estimate has been prepared by Snowden Mining
Industry Consultants ("Snowden") in Canada for the Henry's Hill prospect at the
company's 100% owned Rio Blanco Project.  Snowden reports that Henry's Hill
contains a combined (Indicated + Inferred) resource of 177 million tonnes
grading 0.98% copper, at the 0.70% total copper cut off, containing
approximately 1.7 million tonnes (3.8 billion pounds) of copper within a global
resource of over 1 billion tonnes at 0.58% copper.


  Cut-off           Combined Resource              Indicated Resource             Inferred Resource
    % Cu         Tonnes           Grade          Tonnes           Grade          Tonnes         Grade
                  '000            % Cu            '000            % Cu            '000          % Cu
    0.70         176,700          0.98           161,000          0.98           15,700         0.98
    0.50         662,200          0.69           476,300          0.72           185,900        0.63
    0.30        1,071,700         0.58           723,100          0.61           348,600        0.52



The resource at Henry's Hill includes a high-grade core within this larger
mineralized envelope containing 65 million tonnes grading 1.26% copper.
Furthermore the Henry's Hill target remains open in several directions and a
follow-up program of infill drilling is designed to test the continuity and
extensions of the copper mineralization in order to amplify and further qualify
the resource.

The resource statement will form an integral part of the pre-feasibility study
that is due for completion in September 2003. This study will define the
economics of a mining operation at Rio Blanco and determine a range of capital
and operating costs for the operation.

Chris Eager, Managing Director and CEO of Monterrico, stated: "Monterrico is
delighted with the initial Mineral Resource Estimate, considering only part of
this large porphyry system has been tested. In particular our confidence is
bolstered by the amount of high-grade near surface secondary copper given its
potential to enhance the economics of the project start-up.   We are pleased to
report that Monterrico is close to achieving its target of defining a resource
of 200 million tonnes at 1% copper and we are confident of exceeding this target
during feasibility drilling."

                                      Ends





For further information:



Chris Eager, Chief Executive,
Monterrico Metals plc               Tel: 020 7448 5088/ Mobile: 07903 158 301

Keith Irons,
Bankside Consultants                Tel: 020 7444 4155/ Mobile: 07885 356 639


Technical NOTE

Monterrico has completed 31 widely spaced drill holes 13,987 metres at Henry's
Hill. As the physical dimension of target area is 1.5km long and up to 600m
wide, the approach has been to drill holes on a grid of 150 x 150 metres.



This latest round of drilling, combined with the previous exploration by
Cyprus-Amax (1996/98), has successfully elevated >90% of the resource estimate
into the Indicated category (at 0.7% Cu cutoff).

Snowden's Mineral Resource estimate for Henry's Hill has been determined in
accordance with the JORC Code (1999) for Reporting on Mineral Resources and Ore
Reserves.

The resource estimate was carried out using ordinary kriging into domains based
upon the copper oxidation state, which is known to be the primary control on the
localisation of mineralisation.  Snowden carried out the estimate within an
interpreted 0.3% total copper envelope and within a similar soluble copper
envelope, and estimated both total copper and soluble copper grades.




   Cut-off                 TOTAL                   Indicated Resource             Inferred Resource
     % Cu          Tonnes          Grade          Tonnes         Grade          Tonnes         Grade
                    '000            % Cu           '000           % Cu           '000           % Cu
Soluble Copper Envelope

     0.70          88,900           1.06          87,300          1.06          1,600           0.95
     0.50          218,200          0.82         181,200          0.85          37,000          0.65
     0.30          316,100          0.72         251,400          0.76          64,700          0.58
Total Copper Envelope

     0.70          176,700          0.98         161,000          0.98          15,700          0.98
     0.50          662,200          0.69         476,300          0.72         185,900          0.63
     0.30         1,071,700         0.58         723,100          0.61         348,600          0.52

All drill core samples were assayed by SGS (Peru) S.A., an independent ISO 9002
certified laboratory located in Lima. ALS-Chemex prepared two certified
standards and a blank that were used to ensure assay quality. The analytical
method was a three acid (partial digestion) assay analysis for the copper with
an atomic absorption finish. Monterrico's internal Drill Core Sampling and
Analysis Protocols were employed to ensure sample handling integrity, quality
assurance and quality control. The Competent Person who supervised the design
and conduct of work performed at Rio Blanco was Geoffrey Keyte, Chief Geologist
and Project Manager.




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