Drilling Report

RNS Number:6810T
Monterrico Metals PLC
29 December 2003


                            Monterrico Metals plc

           First assay results from Rio Blanco Feasibility Study



LONDON: 29 December 2003 - Monterrico Metals ("Monterrico" or the "Company")
(MNA.L) is pleased to report the successful start-up of the Feasibility Study on
it's 100% owned and operated Rio Blanco Copper Project in northern Peru ("Rio
Blanco").



Drilling at Rio Blanco is now focused on defining a mineable reserve on the
Eastern Slope of Henry's Hill. The objective is to convert in part the current
indicated and inferred resource of 177 million tones @ 0.99% Cu  into a
proven and probable ore reserve.  Monterrico is now drilling on an approximate
75m x 75m grid to quantify and qualify the distribution of the enriched
(supergene) and primary (hypogene) copper mineralization.



Assay results for the initial two holes of the proposed 20,000 metre infill
program for the Feasibility Study are tabulated below. It is important to note
both holes were terminated in mineralization.


RB - 50 (290degrees / - degrees)       From  -    to (m)       Interval (m)      Cu %       Mo %      Cu % equiv*
                                        
Supergene ONLY                          92         218              126.0         0.94      0.015         1.03
                                   incl   174      204                30          1.48      0.014         1.57
                                       
Hypogene ONLY                          218        411.5             193.5         0.51      0.016         0.61
                                   incl.  228      276                48          0.71      0.021         0.84

Supergene + Hypogene                    92        411.5             319.5         0.68      0.016         0.78






RB - 51  (250 degrees / - 65 degrees)    From  - to (m)        Interval (m)      Cu %        Mo %      Cu 5 equiv*
                               

Supergene ONLY                           194      254               60           1.10       0.013         1.18
                                      incl. 210   250               40           1.31       0.012         1.38
                                

Hypogene ONLY                            245     338.3             84.3          0.50       0.013         0.58
                                     incl. 292    310               18           0.72       0.018         0.83

Supergen + Hypogene                      194     338.3            144.3          0.75       0.013         0.83


* Copper equivalent grades have been calculated using current metal prices
(US$1.00/lb. for copper and US$6.20/lb for molybdenum); %Cu equiv. = %Cu + %Mo x
6.2.



Monterrico recently announced the results of the Pre-Feasibility Study to
develop a large-scale, open cut mining and milling operation at Rio Blanco. The
report demonstrated the technical and economic viability of processing 10
million tonnes of ore to produce 100,000 tonnes of copper in concentrate per
year. This process also allows the recovery of valuable bi-products including
molybdenum and silver.  Monterrico is now assessing the grade of molybdenum and
silver that may be recovered in parallel to producing the copper concentrate.
The recovery and sale of molybdenum and silver in concentrate would result in
additional revenues that would further improve the project economics.  As result
analysis of copper and molybdenum is now reported and the total copper
equivalent grade quoted.



The "Karina" exploration tunnel, driven along the 2,350m level, has been
terminated at 322.4 meters midway across Henry's Hill.  Monterrico earlier
reported an interval of 90 meters @ 1.10% copper from the original 171 meters of
advance. Laboratory results for the final 151.4 meter extension has received and
include 60 meters at an average copper (only) grade of 1.23%. The contribution
of molybdenum can be clearly seen as a valuable credit to the overall project
economics.




       Tunnel KARINA          From     -    to (m)         Interval (m)      Cu %        Mo %      Cu $ equiv*
                               28             322.4         294.4            0.91       0.014         1.00
ALL Supergene                incl. 64           154            90            1.10       0.006         1.14
                             incl. 170          230            60            1.23       0.029         1.41







Monterrico recently raised GB#10.8 million, principally to fund the definitive
Feasibility Study for Rio Blanco, which is scheduled for completion in early
2005.



Mr Chris Eager, managing director, said "The first drill holes in the infill
drilling campaign have further confirmed substantial widths of ore grade
mineralization both in the enriched blanket and in the underlying primary zone.
The scenario of building a concentrator at Rio Blanco has the advantage that we
can factor in bi-product credits, increasing project revenues.  Drilling deeper
into the primary mineralization will increase Rio Blanco's resource base
significantly".







                                      Ends

For further information:



Chris Eager, Chief Executive,

Monterrico Metals plc               Tel: [phone]/ Mobile: [phone]

Keith Irons, Bankside Consultants   Tel: [phone]/ Mobile: [phone]

Richard Chase, Ambrian Partners,    Tel: [phone]




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