16th May 2007 07:01
Medusa Mining Limited16 May 2007 16 May 2007 MEDUSA MINING LIMITED Co-O MINE UPDATE: DEVELOPMENT and RESEARCH Medusa Mining Limited ("Medusa" or the "Company"), the Australian based companyoperating and developing gold mines in the Philippines, advises that itanticipates achieving production of 10,000 ounces for the current June quarter(annualised 40,000 ounces). Re-estimation of the Co-O Mine resources is due inthe third quarter. Development Continuing development on the 3,050 metre level (100 metres below the aditlevel) confirms the vein interpretations from the first deep drill holes (MD 20and 23) on the east side of the Oriental Fault as described in the announcementof 28 February 2007. Driving north from the bottom of the 3W shaft hasintersected the North Vein, which was known on the west side of the OrientalFault, and the new Edphil Vein, both of which have returned good grades. At the 3,010 metre level, 140 metres below the adit level, development on theCentral Vein has shown it is up to 4 metres wide, and generally averages inexcess of 20g/t gold. The Central Vein consists of dominantly colloform white to bluish to greyishbanded chalcedony (low temperature quartz), quartz and lesser calcite. It alsocontains natural cavities lined with quartz crystals, which in places are up toman-sized. On the 3,010 metre level, bands of high grade "black leaders" (local terminology),which commonly contain gold grades of 200 - 400g/t, have been located in theCentral Vein. The black leaders consist of sphalerite-galena-minor pyrite andrare chalcopyrite and are usually associated with colloform chalcedony andcalcite. Research The Co-O gold deposit is located in the northern section of a large alterationanomaly as determined by airborne magnetics. In 2006 the Company, in cooperation with the Centre for Exploration Targeting atthe University of Western Australia, contracted the services of a postgraduateresearch geologist to undertake detailed studies, initially on the Co-O Minefollowed by other deposits and prospects. The aim of the research is tounderstand the depth potential of the Co-O veins through determination of thetemperature of vein deposition, vein and alteration mineralogies and othercharacteristics within the regional structural framework of the mineralisingPhilippine Rift Fault. In addition, these results would be utilised to determineif they could be used as vectors to locate potential porphyry copper goldintrusives which the Company interprets may be the source of mineralisationwithin the Co-O aeromagnetic anomaly. In summary, the work to date has identified the following important features: •The Co-O veins are comprised of two gold bearing phases, the first being a quartz- chalcedony +/- calcite phase deposited at a temperature of approximately 180 degrees C, and a second phase comprising blocky calcite-quartz +/- barite, likely to be deposited from boiling fluids in a temperature range of 200-250 degrees C; •The top of the Co-O mineralisation formed most probably in the upper 300 metres of the crust and therefore the veins are essentially fully preserved (meaning the veins have been subjected to minimal erosion). This implies that to date the drilling is in the upper parts of the vein system and does not appear to have reached the bottom of the mineralisation, with two of the deepest intersections east of the Oriental Fault returning high grades (2.10 metres at 15.05g/t gold in MD 28 and 2.70 metres at 87.6g/t gold in MD 34) at approximately 300 metres vertically below the mine adit. Geoffrey Davis, Managing Director of Medusa, commented: "The Company is pleased to be able to report rising production. The continuingunderground development is supporting the results obtained from recent drillingwhich will, in turn, support the new resource estimate anticipated to becompleted during the next quarter." Maps and photographs which accompany this announcement can be viewed in the ASXversion of the announcement on the Company's website: www.medusamining.com.au The information in the above announcement was compiled by Geoff Davis, who hassufficient experience which is relevant to the style of mineralisation and typeof deposit under consideration and to the activity which he is undertaking toqualify as a Competent Person as defined in the 2004 Edition of the"Australasian Code for Reporting of Exploration Results, Mineral Resources andOre Reserves". Geoff Davis consents to the inclusion in the report of thematters based on his information in the form and context in which it appears. For further information, please contact: Medusa Mining Limited +61 8 9367 0601Geoffrey Davis, Managing DirectorRoy Daniel, Finance Director Ambrian Partners +44 (0)20 7776 6417Richard Brown / Richard Greenfield Bankside Consultants +44 (0)20 7367 8888Michael Padley / Daniela Hale This information is provided by RNS The company news service from the London Stock ExchangeRelated Shares:
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