RNS Number:9040S
Monterrico Metals PLC
05 December 2003

                             Monterrico Metals plc
                        Rio Blanco Pre-feasibility Study

      Strong copper prices provide additional lustre to the results of the
             Pre-feasibility Study at Rio Blanco in northern Peru.

LONDON: 05 December 2003 : Monterrico Metals plc ("Monterrico" or the "Company")
is pleased to release highlights from the Pre-feasibility Study which examined
the economics for the development of the Company's 100%-owned Rio Blanco Copper
Project ("Rio Blanco or the "Project").

Discounted cash-flow analysis using data from the Pre-feasibility Study
indicates a pre-tax Project Net Present Value of US$320 million at a discount
rate of 10% and an internal rate of return of 33% using a copper price of 90
cents per pound.

The Pre-feasibility Study was compiled by GRD Minproc whose conclusions where
drawn from individual reports by Snowden Mining Industry Consultants, Vector
Engineering, SGS Lakefield, Golder Associates, Water Management Consultants and
Minproc.

The report appraised four process design options for the development of the
Project, as it is currently understood. The report concluded that the best
financial return for the lowest technical risk was to mine 10 million tonnes of
ore per annum (27,000 tonnes per day) using simple open cut technique and
produce a copper concentrate for shipment to a smelter.  Production in this
scenario would average around 100,000 tonnes of copper in concentrate per annum
in the first seven years.

The key advantages at Rio Blanco are;

*        The possiblity to mine higher grade ore for the first five years of
         production (at an average grade of 1.13% Cu)

*        Rapid payback of capital around 3 years and long mine life, 32 years.

*        Waste to Ore ratio very low at around 0.7:1 over life of mine.

*        Simple metallurgy allows for high recoveries of around 90 - 95% and the
         production of a clean high-grade concentrate (30 - 38% Cu)

*        Estimated capital cost for the project is US$191 million, which is
         modest for its size due to simple mining and processing.

To date, Monterrico has not taken into account the molybdenum present in the
resource.  Molybdenum may be extracted in the concentration process and would be
a valuable by-product.  The company intends to calculate a molybdenum resource
as the part of the feasibility study, and this has the potential to further
improve the economics of the project.

The Company has recently secured GBP10.2 million (net) to fund the Bankable
Feasibility Study. Drilling contractors have initiated the 20,000 meter infill
drill program to define proven and probable ore reserves. Tunnelling contractors
are extending the "Karlita" tunnel and are presently at 270 meters through
Henry's Hill.  Monterrico currently has 20.17 million shares in issue trading at
around 168p and an undiluted market capitalisation of GBP33.9 million.

Chris Eager (CEO) said:  "The timing for the Project couldn't be better, there
is sustained international demand for clean high grade copper concentrate and
the outlook for rising copper prices.  Rio Blanco looks very attractive at the
current copper price (around 95 c/lb) and sensitivity analysis indicates that
the project could generate robust cash-flows at much lower prices. The
Feasibility Study has begun and results from both the drilling and tunnel should
be released prior to Christmas."

Contact:

Christopher Eager, Monterrico Metals           +44 20 7448 5088
Keith Irons, Bankside Consultants              +44 20 7444 4155 / 07885 356 639
Richard Chase, Ambrian Partners                +44 20 8528 1456


Technical note

The cost estimations have been completed to a pre-feasibility level of
confidence which is estimated to be within plus or minus 25%.

The discounted cash-flow analysis was based on the following assumptions;

Mine Production
                                                         First five years  First ten   First twenty     Total
                                                                             years        years      thirty-two
                                                                                                        years
Tonnes of ore mined                                                54,117      115,264      247,146       346,168
Tonnes of waste mined                                              90,061      147,564      214,626       251,915
Waste to ore ratio                                                   1.66         1.28         0.87          0.73

Tonnes ore processed             t.000                             50,245      100,378      191,574       315,797
Grade                            %                                   1.13         0.99         0.90          0.78
Concentrate grade                %                                     38           38           38            38
Tonnes of concentrate            t.000                              1,350        2,359        4,066         5,853
Tonnes Cu in concentrate         t.000                                513          896        1,545         2,224
Pounds Cu in concentrate         lbs,000                        1,130,728    1,976,144    3,406,109     4,903,723



Annual Operating Costs
                                                         First five years  First ten   First twenty     Total
                                                                             years        years      thirty-two
                                                                                                        years
Physicals
Ore mining rate                  t,000 per yr                      10,823       11,526       12,357        10,818
Waste mining rate                t,000 per yr                      18,012       14,756       10,731         7,872
Ore treatment rate               t,000 per yr                      10,049       10,038        9,579         9,869
Average ore grade                %                                   1.13         0.99         0.90          0.78
Average production of Cu in cons t,000 per yr                         103           90           77            70

Site operation costs
Average mining cost              $/t of ore                          3.17         2.93         2.77          2.20
Average treatment cost           $/t of ore                          3.07         3.07         3.07          3.07
Average admin cost               $/t of ore                          0.30         0.30         0.30          0.29
Average site costs               $/t of ore                          6.54         6.30         6.14          5.56
Average site costs               c/lb of CU                          31.5         34.8         37.1          37.1

On costs
Trucking, shipping, marketing    c/lb of Cu                           5.0          5.0          5.0           5.0

TC/RC
Payable copper                   %                                   96.5
TC                               $/t                                   60
RC                               c/lb                                0.06
Total TC/RC                      c/lb                                13.2         13.2         13.2          13.2

Total costs                      c/lb                                49.7         52.9         55.2          55.2








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