Metminco Regulatory News (MNC)

Metminco Limited (LSE: MNC)

("Metminco" or "the Company")

Deep drilling at Los Calatos confirms classic major porphyry system

Metminco is pleased to announce that ongoing drilling at the Company's flagship asset, the Los Calatos copper-molybdenum porphyry project in southern Peru, has confirmed that the project is a classic major porphyry system. Significant intersections since the March 2011 quarterly report include:

CD 27 : 798 metres @ 0.50% Cu and 288ppm Mo 1

Including 406 metres @ 0.65% Cu and 442ppm Mo

CD 31 : 1,340 metres @ 0.64% Cu and 360ppm Mo 1

Including 255 metres @ 1.68% Cu and 310ppm Mo

(1 = further assay results awaited)

Los Calatos Project

The current drilling programme at Los Calatos is specifically designed to provide detailed information on the extent of the alteration system operating at Los Calatos including the width and depth potential of the mineralised porphyry system.

To date 10 drill holes totalling approximately 13,000 metres have been completed (or are close to completion) in the current 50,000 metre phase 3 drill program (Table 1). In order to test the full extent of the porphyry system evident at Los Calatos, drilling has been undertaken to depths of up to approximately 2,000 metres. Currently 4 drill rigs are operating at Los Calatos with a further drill rig expected to be operational by mid Q3 2011.

The main area of interest at Los Calatos is defined as the ¨LIX capping¨ which is now understood to be the controlling feature for the mineralisation. This zone is vertical and is developed to considerable depth, likely greater than 2,000 metres.

The block model used in the estimation of resources announced in July 2010 for Los Calatos included drill holes to a vertical depth below surface of 1,100 metres and a width of mineralisation of up to 500 metres. In the results to date, significant intercepts of mineralisation have been encountered to a vertical depth below surface of 1,700 metres while the width of mineralisation within the porphyry zone increases from approximately 700 metres at surface to approximately 1,000m at a vertical depth of 1,500m in the central part of the porphyry system.

Drilling into the diatreme has revealed that this part of the system is generally mineralised at a lower molybdenum grade than the porphyry zone, as is evidenced by drill holes CD 28 and CD 30. This is also true of the porphyry zone in the north-west where the LIX capping is narrow and less well developed, as evidenced by CD 29.

The Company will now focus on completing drill holes marked 1 to 15 (23,000 metres of drilling) to test the full strike length of the "LIX capping"

On completion of these drill holes the Company expects to be in a position to commence an in-fill drill program of the mineralised system with a view to fully defining the mineral resources at Los Calatos by the end of 2012. The Company will then commission a pre-feasibility study on the project.

Chilean Projects

In Chile Metminco has commissioned Major Drilling to undertake 16,000 metres of RC drilling and 12,000 metres of diamond drilling at the Mollacas, Vallecillo and Camaron projects by the end of 2011. Drilling at Vallecillo and Camaron will be preceded by IP and ground magnetic geophysical surveys to help refine drill targets.

Table 1 : Los Calatos copper - molybdenum project : Phase 3 drill hole assay data.

 (1 = hole in progress and/or assays outstanding)

(2 = intersection interval excludes minor barren porphyry dykes)

A copy of the announcement including diagrams can be downloaded from the Company's website www.metminco.com.au

For further information contact:

South America:

William Howe - Managing Director Ph: +56 (2) 411 2600

Australia:

Phillip Wing - Executive Director Ph: + 61(0) 412 254 704

Philip Killen - Company Secretary & CFO Ph: + 61(0) 408 609 916

United Kingdom:

Tim Read - Director Ph: +44 (0) 777072 1809

Nomad and Broker - Investec Bank plc

Stephen Cooper / David Currie (Investec Bank plc) +44 (0)20 7597 4000

Financial Public Relations Consultant - Buchanan

Tim Thompson / James Strong / Katharine Sutton +44 (0) 20 7466 5000

About Metminco:

Metminco is a dual ASX and AIM listed company with a portfolio of copper and gold projects in Peru and Chile. The Los Calatos project located in southern Peru has JORC compliant resources of 926 million tonnes, consisting of Indicated Resources of 111 million tonnes at 0.39% Cu and 380ppm Mo and Inferred Resources of 815 million tonnes at 0.37% Cu and 260ppm Mo (at a 0.2% copper cut-off grade).

The Chilean assets include a 100% interest in the Mollacas copper leach project with JORC compliant resources of 17 million tonnes consisting of Indicated Resources of 7.2 million tonnes at 0.56% copper and Inferred Resources of 9.8 million tonnes @ 0.52% copper (at a 0.2% copper cut-off grade); and a 50% interest in the Vallecillo gold zinc project with JORC compliant resources of 10.1 million tonnes consisting of Indicated Resources of 7.9 million tonnes @ 1.14g/tAu; 11.4g/tAg; 1.32% Zn; 0.29% Pb and Inferred Resources of 2.2 million tonnes @ 0.78g/t Au; 8.2g/t Ag; 0.58% Zn; 0.26% Pb (at a cut-off grade of 0.3g/t Au).

* Cut off grade of 0.2% Cu. Copper equivalence (CuEq), in-situ, assumes a ratio of Mo/Cu prices of 5.

Competent Persons Statement

The information in this report that relates to Exploration Results and Mineral Resources is based on

information compiled by Colin Sinclair, Bsc, MSc, who is a Member of the Australasian Institute of Mining and Metallurgy and is a full-time employee of the Company as General Manager Exploration.

Colin Sinclair has sufficient experience (over 30 years) 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.