(a) Where a person who commences to carry on a trade of working a qualifying mine has incurred exploration expenditure and that expenditure was not incurred in connection with the qualifying mine, then, subject to paragraph (b), in taxing the trade for the chargeable period in which the person commences to carry on the trade, there shall be made an allowance of an amount equal to the amount of that expenditure.
(b) For the purposes of paragraph (a), no account shall be taken of exploration expenditure incurred before the 1st day of April, 1990, if the expenditure was incurred more than 10 years before the date on which the person commences to carry on the trade of working the qualifying mine.
(2) Where in a case referred to in subsection (1) the person concerned is a body corporate and there was or is, after all or part of the expenditure referred to in that subsection had been incurred by the body corporate, a change in ownership (within the meaning of Schedule 9) of the body corp
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