Alba Mineral Resources plc (LON:ALBA) in the announcement made on 16 December 2016, reported the results of a microgravity study and portable XRF shallow soil sampling programme from the Limerick base metal project (“Limerick” or the “Project”) in Co. Limerick, Republic of Ireland. Interpretation of the gravity data suggests the presence of gravity anomalies consistent with brecciation of the host limestone, with zinc and lead anomalism in shallow soil samples collected above or adjacent to gravity anomalies. The Company has now received the full laboratory assay results from select soil samples taken during the recent programme.
Highlights
· Assay results confirm four main areas of anomalism
· Most pronounced anomalism for copper-silver-arsenic (Cu-Ag-As) similar to that found at former Gortdrum copper-silver (Cu-Ag) mine 25 km due east
· Gortdrum was mined for copper-silver-mercury (Cu-Ag-Hg) between 1967 and 1975, producing 3.8 million tonnes containing 1.19% Cu and 25.1 g/t Ag
· This target in particular will be the focus of the next stage of work
Four areas displaying coincident metal anomalism were noted. One area with zinc-silver-manganese-barium (Zn-Ag-Mn-Ba) anomalism over a north trending, 600 x 200 m zone is centred over a gravity high and is interpreted to be near-surface bedrock. Three hundred metres to the west of this anomaly, a 400 m by 200 m east-trending lead-silver-zinc (Pb-Ag-Zn) anomaly occurs. The eastern edge of this anomaly was drilled by Teck Ireland during a JV with Alba, but did not encounter mineralization. A barium (Ba) anomaly is present at the margins of a possible zone of brecciation (interpreted from the gravity data). Barite mineralization is often associated with mineralization in the Irish orefield, and sometimes forms a primary ore, such as the Ballynoe mines, near Silvermines in Co. Tipperary (5.13 Mt at a grade of 90% BaSO4).
The most pronounced anomalism occurs over a 600 m by 200 m area, 2 km from the village of Bruff. At this location, copper-silver-barium (Cu-Ag-Ba) anomalism follows the trace of a mapped east-west trending fault, and is intersected by a northeast-trending zone of copper-arsenic-antimony-silver-barium (Cu-As-Sb-Ag-Ba) anomalism coincident with the mapped contact of the Argillaceous Bioclastic Limestone (“ABL”) and Waulsortian Limestone Formation. The ABL-Waulsortian contact is the main target for zinc mineralization in Ireland. However, the metal assemblage is similar to that encountered at the former Gortdrum copper-silver mine, located 25 km due east of the anomaly. Gortdrum was mined for copper-silver between 1967 and 1975, producing 3.8 million tonnes containing 1.19% copper and 25.1 g/t silver, as well as recoverable quantities of mercury. Ore from Gortdrum contained four principal minerals, mercurian tennantite, chalcopyrite, bornite, and chalcocite. Mercurian tennantite also contains appreciable concentrations of arsenic. The metal anomalism noted over this target, with the exception of mercury, matches the principal metals found at Gortdrum, i.e. copper-silver-arsenic-antimony (Cu-Ag-As-Sb). This new target will now form the focus for additional work on the licence.
The Company is now considering the next stage of work on the Limerick Project which may include conducting several Induced Polarization (IP) lines over potential targets not previously tested. If warranted, follow-up exploration drilling will take place to determine the cause of geochemical and geophysical anomalism.
Michael Nott, Alba Mineral Resources plc Chief Executive Officer, commented: “The four principal anomalies that have been identified provide us with targets for follow-up exploration. In particular, the copper-silver-arsenic-antimony anomaly discovered matches quite closely the profile of the copper-silver-mercury mine at Gortdrum, just 25km to the east. Gortdrum was mined for copper-silver between 1967 and 1975, producing 3.8 million tonnes containing 1.19% copper and 25.1 g/t silver, as well as recoverable quantities of mercury. This is further evidence that we are in the right address geologically. This target will be our focus for ongoing work at Limerick.”
