Last checked at 26 Apr 2010 07:00
Red Rock Resources PLC
Drilling Results: Migori
Date: 23rd April 2010
Red Rock Resources plc ('Red Rock' or the 'Company') the mining exploration and mineral investment company with interests in steel feed, uranium, and gold, announces new sample results from its Migori gold project in Kenya.
Base metal results have been received for samples from the December 2009/January 2010 drilling programme on the Macalder tailings dam; and from grab samples collected during the February 2010 regional prospecting exercise. Further results from reverse circulation drilling are awaited.
The results confirm the economic potential of the tailings, and the existence of further exploration targets suitable for early follow-up in the eastern license and at Nyarongi.
http://www.rns-pdf.londonstockexchange.com/rns/7428K_-2010-4-23.pdf
Approximately 458 metres were drilled on the tailings dam (32 holes on a 25x25 metre grid with 6 infill holes). Drill depth varied across all hole between a maximum of 20 metres and minimum of 6 metres. Two holes only reached 1.5 metres and 3 metres due to hard ground. A random selection of 43 samples from all the holes across the dam were selected for ICP analysis in order to determine the base metals present; at what concentrations; and how they vary between the identified major zones i.e. the sulphide and calcine. Gold and silver grades for these samples are currently awaited as they must undergo fire assay analysis. This data will help to determine which processes are required for testing the calcine and sulphide when they are sent for metallurgical analysis and leach tests in Perth, and ultimately the mining processes required. The results in the following table display the suite of base metals present.
Results from ICP analysis of the tailings dam (weighted averages)
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| Cu (%) | Co (%) | Pb (%) | Zn (%) | Au | Ag |
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Sulphide 22 samples |
0.33 |
0.07 |
0.17 |
0.76 |
awaited |
awaited |
|
Calcine 19 samples |
0.61 |
0.05 |
0.53 |
0.67 |
awaited |
awaited |
|
Ox Zone 1 sample |
0.48 |
0.11 |
0.14 |
0.78 |
awaited |
awaited |
|
Gossan 1 sample |
0.08 |
0.01 |
0.02 |
0.07 |
awaited |
awaited |
The oxidised surface and the gossan tailings at the base are volumetrically insignificant. Therefore, they will be mined in bulk with the calcine and sulphide tailings, and not separately. The above table shows that the greatest variability between the sulphide and calcine is in the copper and lead concentrations (difference of 0.28% Cu and 0.36% Pb). The other base metals are at approximately similar concentrations however this may not be homogeneous across the whole of the tailings if the concentrations also vary with distribution in the dam. For the metallurgical test work, bulk composites will be made with samples from different areas of the tailings dam (e.g. east calcine zone, west sulphide zone etc.) in order to determine whether there is any variability with distribution.
Hand-grab samples were collected at new BIF-related targets in the eastern licence, which has had little modern exploration at Francis, Karutiange, and Lake Bush North, as well as at the Nyarongi prospect in the western licence where historic soil sampling results show good mineralisation grades at surface. They were sent to the laboratory in Mwanza for gold assaying and the results have now been received.
From the Francis prospect, 2 out of 3 hand-grab samples show mineralisation at measured grades of 5.57 g/t Au in one sample and 44-46.3 g/t Au in the other. These samples contained milky white quartz associated with abundant fresh, and partially oxidised, pyrite and were obtained from a waste dump from colonial era mining. Samples from Karutiange and Lake Bush gave maximum measured grades of 0.76 g/t Au and 0.48 g/t Au respectively.
The samples from these 3 targets showed leaching after pyrite and so greater mineralisation may exist at depth according to the gold-associated BIF model whereby gold is leached from surface and concentrated at depth. A more rigorous exploration programme, in order to fully investigate the extent, and nature, of these prospects, is planned.
Of the Nyarongi samples, 8 out of 11 contained measured grades between 0.62-15.6 g/t Au. These 'hand-grabs' were picked up just east of the soil sample anomaly outlined by Auvista in the mid-90's, thus extending the area of the Nyarongi prospect.
The current trenching programme at Mirema has exposed the mineralised structure (a replaced BIF horizon) and is being mapped and sampled. Explosives will be used to better expose the materials and to facilitate sampling at depth, not just on surface. This is necessitated by the degree of supergene leaching seen on the exposed surfaces that show abundant negative pseudomorphs after pyrite.
The tailings samples are currently being prepared for export to Perth for the metallurgical test work and acid rock drainage tests are being conducted at the tailings dam.
The Migori gold project consists of a 60% farm-in interest in 63km of a greenstone belt in Southern Kenya near the Tanzanian border, and interests in contiguous areas. The area has a NI-4301 compliant Indicated Resource of 1,172,000 oz gold.
The technical information in this announcement has been prepared by Kamini Manick, MESci, and approved for release by Helen Salmon, BSc, FGS, who is a qualified person as defined in the Note for Mining and Oil & Gas Companies, June 2009, of the London Stock Exchange.
For further information contact:
| Red Rock Resources plc |
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| Andrew Bell, Chairman | 0207 402 4580/07766 474849 |
| John Watkins | 07768 512404 |
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| Nominated Adviser |
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| Religare Capital Markets |
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| Peter Trevelyan-Clark/Ben Jeynes | 020 7444 0800 |
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| Broker |
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| Simple Investments Ltd |
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| Nick Emerson, Renato Rufus | 01483 413500 |
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| Public Relations |
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| City of London PR |
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| Ron Marshman | 020 7011 9411 |
Updates on the Company's activities are regularly posted on its website www.rrrplc.com.