The Supreme Court dismissed Tara Mines Limited’s appeal over corporation tax assessments for the years ended 31 December 1978 to 31 December 1988, affirming a High Court order that allowed an appeal by the Inspector of Taxes. The court held that Tara’s above-ground processing activities were mining operations for the purpose of the export sales relief restriction in section 58(9) of the Corporation Tax Act 1976.
The dispute concerned whether income from lead and zinc concentrates exported by Tara could qualify for export sales relief. Tara extracted ore near Navan, County Meath, then processed it at an on-site plant into concentrates for sale to smelters abroad. The ore itself was not sold, and the judgment records that transporting it elsewhere for processing would have been uneconomic.
The Appeal Commissioners had found that mining and processing were distinct activities of similar scale, with neither subsidiary to the other. They concluded that Tara sold the manufactured concentrates, rather than the output of its mining operations, and that its trading income qualified for relief. The Inspector appealed, arguing that all of Tara’s activities through production of the concentrates were mining operations.
The High Court allowed the Inspector’s appeal. Tara then appealed to the Supreme Court, which considered whether processing after extraction could still fall within “mining operations”. The court said the term has no precise definition and is not limited to underground extraction. Processing may constitute manufacturing and also be a mining operation, depending on its nature and relationship to extraction, considered in the context of the purpose of the mining venture.
The Supreme Court held that the Commissioners’ findings made the outcome clear: Tara’s business was undertaken to produce marketable concentrates on site, because the extracted ore had no economic market. On those findings, the above-ground processing constituted mining operations, even though it also manufactured goods under the 1976 Act.
Section 58(9) barred export sales relief in respect of corporation tax payable on income from mining operations. The Court said the provision covered this overlap between manufacturing and mining, preventing relief on income from the activity. It dismissed Tara’s appeal and affirmed the High Court order. The judgment does not set out a new tax assessment amount.