Minco PLC Regulatory News (MIO)

15 Jan 2007 07:00

Minco PLC15 January 2007 Press Release Minco Releases Preliminary Sulphide Resource Estimate and Drilling Results for the Bilbao Project London, 15 January 2007 - Minco plc (MIO), the AIM quoted precious and basemetals exploration and development company today announces a preliminaryresource estimate and an update on its sulphide drilling and evaluationprogramme at the Bilbao zinc-silver-copper-lead project in Zacatecas, Mexico. Highlights • Inferred Resource of 2.8 million tonnes at an average grade of 3.88% zinc, 2.39 lead, 0.26% copper and 88.7g/t silver (6.32% zinc equivalent). • Recent drilling and assaying confirms that the known zinc-silver-lead-copper mineralisation at Bilbao remains open to the south and west. • A Prefeasibility Study based on an updated resource evaluation and ongoing metallurgical test work is to be completed in the coming months. • To date, a total of 31 diamond drill holes have been completed. Roger Turner, Executive Chairman of Minco commented "Today's initial resourceestimate for Bilbao forms a key component of our continuing pre-feasibilitystudy. We look forward to moving Bilbao a further step closer to a productiondecision as our drilling programme at Bilbao continues to intersect grades andwidths of economic significance. The mineralisation remains open both towardsthe south and along strike towards the west. We are continuing our efforts todefine the sub-surface extent of these mineralised structures within ourextensive licence area and we look forward to reporting more positive results inthe near future." Resource Estimate A Datamine study based on the currently available drill hole data has beencompleted by our independent consultant, Dr Jeff Aucott. At a 3% Zincequivalent cut-off grade and a sulphide to oxide boundary 100 metres belowsurface, this study has outlined an inferred resource of 2.8 million tonnes at average grades of:- 3.88% zinc, 2.39 lead, 0.26% copper and 88.7g/t silver (6.32% zinc equivalent). The resources, with a drill hole grid spacing of approximately 70 metres, areclassified as inferred. 23 holes have been used in the evaluation. New drillhole assay data for another four holes (B6B, X18, X21, X22) were received onJanuary 6th and is now being entered into the resource database. It isanticipated that this data will extend the resource model to the south and east.Results from another four holes (X23, X24, X25 and X26) are awaited and X27 isbeing drilled. The assays should be available in the next month. There are two main sulphide ore bodies which dip to the south. They have beendefined using a zinc equivalent cut-off grade of 3.0 percent and a minimuminter-ore body waste parameter of 3 metres. The minimum vertical ore thicknessused is two metres. The lower ore body is the largest and from the central areaof the deposit, appears to divide into two, sometimes three thinner lenses tothe South and East. The upper ore body is smaller but more consistent andappears to divide into thinner lenses upwards and to the North West as itapproaches the surface. The current maximum depth of the upper sulphide ore body is 270 metres with amaximum drill hole intersection thickness of 27 metres. The maximum depth of thelower sulphide ore body is 290 metres with a maximum drill hole intersectionthickness of 38 metres. There is a sulphide/oxide boundary which can be sharp,over a metre, or gradual over a distance of about 30 metres. There is a zone ofmixed oxides and sulphides which is currently being modelled as the data becomesavailable. No modelling has been completed on the surface oxide zone. In 1994, WattsGriffis & McOuat prepared a resource estimate of the overlying oxide material atBilbao on behalf of Minera Portree amounting to 3.2 million tonnes at an averagegrade of 3.9% zinc equivalent using a 0% cut-off grade. Dr Aucott is currentlyupdating these oxide resource estimates using the current Minco drilling and weexpect to in a position to announce the results in the coming weeks Prefeasibility Study Underway Metallurgical and mineralogical test work is underway on the Bilbao sulphidemineralisation which together with other studies will form a PrefeasibilityStudy which has been commissioned under the leadership of Mr Al Summers, anindependent consulting mining engineer and former Vice President of Operations,Hecla Mining Inc. The results of this study are expected to be available overthe coming months. Latest Drilling Results To date a total of 31 diamond drill-holes have been completed on the Bilbaodeposit during the current drilling campaign. Results for sulphidemineralisation in drill holes X18, X21 and X22 and for oxide mineralisation inhole B6B are reported below. These new intersections confirm thatmineralisation remains open in depth to the south and along strike to the west. The 10 metre intersection in hole X21 averaging 5.30% zinc, 1.65% lead, 0.23%copper with 30 g/t silver, and the 9 metre wide intersection in X18, whichaveraged 3.69% zinc, 1.46% lead with 0.36% copper and 136 g/t of silver areconsidered to be particularly encouraging as they demonstrate that potentiallymineable grades and thicknesses of mineralisation extend through the centre ofthe exploration area. Further, it is encouraging that wider spaced drilling outside of the mainmineralised zone has demonstrated that mineralisation is widespread across theBilbao property. Holes X22 and X25 located respectively 500 metres and 637metres to the southeast of the known mineralisation intersected semi-massivesulphide mineralisation over intervals of 11.85 metres and 2.80 metresrespectively. These intersections are not believed to be part of the mainsulphide body and suggest a separate mineralised zone. Assay for these holesare currently being processed. New Drill Results from Bilbao Hole From (m) To Width (m) Zinc Lead Copper Silver (g/t) (m) (%) (%) (%)Oxide B6B 150.05 153.40 3.35 2.32 1.48 0.17 90Oxide B6B 177.46 181.16 3.70 6.11 0.60 0.17 138Oxide B6B 186.77 189.40 2.63 1.24 0.42 0.10 68Sulphide X18 228.00 237.00 9.00 3.69 1.46 0.36 136Sulphide X21 248.00 254.00 6.00 1.99 3.87 0.04 38Sulphide X21 264.00 266.00 2.00 2.26 4.40 0.30 89Sulphide X21 280.00 290.00 10.00 5.30 1.65 0.23 30Sulphide X22 210.00 211.00 1.00 2.05 0.29 0.84 117 New Drill Intersections from Bilbao (Assays Awaited) Hole From To Width (m) (m) (m)Sulphide X23 252.50 253.80 1.30 Waiting for AssaysOxide X24 136.50 138.80 2.30 Waiting for AssaysOxide X24 154.60 168.80 14.20 Waiting for AssaysSulphide X24 210.60 213.05 2.45 Waiting for AssaysSulphide X24 217.70 222.55 4.85 Waiting for AssaysSulphide X24 224.40 225.75 1.35 Waiting for AssaysSulphide X25 110.50 113.40 2.80 Waiting for Assays Drill Results from Bilbao (Previously Released) Hole From To Width Zinc Lead Copper Silver (m) (m) (m) (%) (%) (%) (g/t)Oxide* B2 10.63 14.30 3.67 1.52 5.35 0.20 77Oxide* B6A 77.50 80.75 3.25 0.87 0.35 0.55 102Oxide* B6A 151.30 153.90 2.60 1.22 1.59 0.03 149Sulphide* B6A 224.00 225.50 1.50 4.21 0.73 0.10 89Oxide* X3 24.00 31.00 7.00 2.50 2.17 0.14 12Oxide* X10 4.00 33.00 29.00 1.54 4.17 0.19 16Oxide* X10 75.00 97.00 22.00 2.35 0.63 0.63 14Oxide* X10 103.00 113.00 10.00 3.32 1.66 0.20 60Sulphide* X10 116.00 141.00 25.00 3.49 2.75 0.26 141Oxide* X11 17.00 42.00 25.00 1.25 2.38 0.10 47Oxide* X11 69.00 73.00 4.00 4.13 0.50 0.29 71Sulphide* X11 153.00 175.00 22.00 6.85 1.39 0.22 100Oxide* X13 31.00 42.00 11.00 2.50 4.62 0.16 33Oxide* X13 132.50 151.80 19.30 8.36 1.52 0.10 23Sulphide* X13 166.95 201.95 35.00 5.57 4.92 0.33 80Oxide X14 41.70 59.00 17.30 4.09 4.05 0.66 91Oxide X14 69.00 76.00 7.00 3.42 4.10 0.60 91Sulphide X14 184.00 193.00 9.00 3.50 1.18 0.31 86Oxide* X15 57.00 60.00 3.00 2.03 3.55 0.05 53Oxide X15 96.00 106.00 10.00 1.49 2.19 0.17 38Oxide X15 118.00 124.00 6.00 1.70 3.69 0.23 161Sulphide X15 207.00 213.00 6.00 1.64 1.59 0.63 136Sulphide X19 194.00 206.00 12.00 2.24 3.53 0.30 37Sulphide X19 237.00 243.00 6.00 3.91 3.53 0.20 37Sulphide X19 256.00 264.00 8.00 2.02 3.04 0.15 140Sulphide X20 194.00 200.00 6.00 3.36 0.84 0.23 114Sulphide X20 208.00 213.00 5.00 4.95 1.66 0.28 81 Qualified Person The above information has been reviewed and verified by Mr. Roger Turner, CEOand Chairman of Minco, for the purposes of the Guidance Note for Mining, Oil andGas Companies issued by the London Stock Exchange in March 2006. Mr. Turner,with 40 years of mining engineering, management and consulting experience,graduated as a mining engineer from the Camborne School of Mines, has an MScdegree in Economic Geology from Leicester University and is a member in goodstanding with the Institute of Materials, Minerals and Mining and a UK CharteredEngineer. About Minco: Minco PLC is an AIM quoted precious and base metals exploration and developmentcompany with silver projects in Mexico and zinc exploration in Ireland. For further information, www.minco.ie or contact:Roger Turner: Executive Chairman +44 (0)20 7397 8155Terence McKillen: Director of Exploration & Business Development +1 416 362 8243/6686Simon Beardsmore: Commercial Manager +44 (0)20 7397 8159Chris Rollason: (UK NOMAD) Collins Stewart +44 (0)20 7523 8350Nick Bias: (UK IR & PR) BuckBias +44 (0)7887 920 530Tom McCormack (Ireland PR) ConneXions +353 (0)1 230 3015 This information is provided by RNS The company news service from the London Stock Exchange