14 June 2001
Geological details of potential new mineral zone west of White Rock
Anglesey Mining plc announces that as a result of ongoing geological reassessment carried out during the past year ended March 31, 2001 it has identified potential for a new zone of mineralisation on its Parys Mountain property. The potential new zone lies at the western end of the property, down-dip from the White Rock Zone, separated by faulting from the major part of the property, and within a few hundred metres of the Morris Shaft.
Over the past few years Anglesey has been undertaking a comprehensive programme of geological reassessment of the Parys Mountain property, including relogging and lithogeochemical sampling of many of the old drill holes. This programme has met with considerable success, has led to a more detailed interpretation of the geology of the deposits and has helped to identify the various sulphide lenses which exist on the property.
Although significant new potential for more mineralisation was identified by this programme during the previous two years to the north and east of the previously known zones, and new exploration targets identified, it has not been possible to undertake the planned exploration drilling due to shortage of finance. In these circumstances, work during the last financial year to March 31, 2001 has concentrated on two major studies on the geology of Parys Mountain. These studies have now led to the identification of a previously unrecognised potential new zone of disseminated/semi-massive mineralisation at depth along the western boundary of the Parys Mountain volcanic complex.
The potential new zone is believed to be located down-dip of the White Rock Zone. The White Rock Zone was partially explored by drilling and by some underground development in the early 1990s and contains a possible mineral resource of 1.5 million tonnes with grades averaging 5.81% zinc, 3.02% lead and 0.41% copper. The White Rock Zone lies within the upper of the three mineral horizons known to be present at Parys Mountain and it is now understood to be identical to, but separated by major faulting from, the Carreg-y-Doll Zone, which is the eastern continuation of the same horizon and from which almost all of the historic underground mining took place throughout the first half of the nineteenth century.
Importantly, modern drilling during the 1960s to the north and down-dip of the Carreg-y-Doll Zone, discovered the Northern Copper Zone, which consists of a lens of disseminated/semi-massive sulphide estimated in the 1960s to contain 30 million tonnes averaging 0.7% copper, with minor zinc and lead. Although deemed to be uneconomic because of its low grade this is a very large single lens of mineralisation, with widths of up to 143 metres averaging 0.98% copper intersected in drilling, and which in fact may not have been adequately assayed for zinc as the occurrence of zinc mineralisation at Parys Mountain was not well recognized at that time.
The potential new zone is comparable to the Northern Copper Zone which lies to the north and down-dip of the Carreg-y-Doll Zone. The White Rock Zone is interpreted as the western continuation of the Carreg-y-Doll Zone, lying at that the same mineralised horizon but separated from it by major faulting. The potential new zone lies to the west and down dip of the White Rock Zone, with the same stratigraphic relationship to the White Rock Zone as the Northern Copper Zone has to the Carreg-y-Doll Zone.
The potential new zone is believed to have been intersected by a single isolated drill hole, A-32, which was drilled in 1978, and recorded an intersection of 6.56 metres averaging 5.06% zinc, 2.44% lead and 0.41% copper; including two intervals which assayed 10.6% Zn, 5.08% lead and 0.72% copper, with 48 grams silver over 1.2 metres; and 10.5% zinc, 4.73% lead, 1.12% copper and 51 grams silver over 0.92 metres, respectively.
In previous geological studies this drill hole A-32 intersection, although out on its own, had been included as part of the Engine Zone horizon, which is the third and stratigraphically the deepest of the three mineralised horizons at the base of the volcanic succession. Almost all of the work completed in the 1980s and early 1990s, including the Feasibility Study, focussed on the Engine Zone, which until now has been believed to be the principal exploration target. However the significance of this intersection in Hole A-32 was not realized until recent re-examination of the drill logs and re-interpretation of the geological relationships indicated that the mineralisation in Hole A-32 is siliceous disseminated to semi-massive material , and thus comparable to the White Rock, Northern Copper and Carreg-y-Doll Zones, rather than the Engine Zone which is dominated by massive sulphide material.
It is not possible at this time, without further drilling, to estimate the size or grade of any such new zone. However, the potential for a continuation of the mineralisation intersected in Hole A-32, within the large unexplored area both up-dip and down-dip from this hole, is considered excellent.
The identification of this potential new zone is very important to Anglesey Mining for a number of reasons.
Firstly, it opens up a second major exploration target, and new zone, to the west, within the Company's freehold owned property, in addition to the exploration target at the Engine Zone horizon to the north and east, which is awaiting drilling.
Secondly, the upper part of this potential new zone lies at a reasonable depth, within close proximity to the existing Morris Shaft and within easy reach of the present underground development. Any such new zone, if confirmed by drilling, could become part of the mine plan for early mining and processing.
Thirdly, the identification of this new zone confirms yet again the unexplored potential of the entire Parys Mountain property. The mineralisation at Parys Mountain has been demonstrated to extend over two and a half kilometres and much of the system remains unexplored or only partially explored. The property has the potential for new discoveries which could make Parys Mountain comparable to other major volcanic hosted polymetallic deposits throughout the world which are substantial sources of zinc, copper, lead, gold, and silver.
Anglesey Mining plans as soon as possible to undertake financing for a drilling programme to explore these new exploration targets which have the potential to transform Parys Mountain into a very significant mineral deposit.
|Anglesey Mining plc
Parys Mountain, Amlwch,
Anglesey, LL68 9RE, UK
|Phone +44 1248 361333