A person resident or ordinarily resident in the United Kingdom who in any chargeable period is entitled to receive any mineral royalties under a mineral lease or agreement shall be treated for the purposes of this Act as if there accrued to him in that period a chargeable gain equal to one-half of the total of the mineral royalties receivable by him under that lease or agreement in that period.

This section shall have effect notwithstanding any provision of section 119(1) of the Taxes Act making the whole of certain kinds of mineral royalties chargeable to tax under Schedule D, F1... .

The amount of the chargeable gain treated as accruing to any person by virtue of subsection (1) above shall, notwithstanding any other provision of this Act, be the whole amount calculated in accordance with that subsection, and, accordingly, no reduction shall be made on account of expenditure incurred by that person or of any other matter whatsoever.

In any case where, before the commencement of section 122 of the Taxes Act, for the purposes of the 1979 Act or corporation tax on chargeable gains a person was treated as if there had accrued to him in any chargeable period ending before 6th April 1988 a chargeable gain equal to the relevant fraction, determined in accordance with section 29(3)(b) of the M1Finance Act 1970, of the total of the mineral royalties receivable by him under that lease or agreement in that period, subsection (1) above shall have effect in relation to any mineral royalties receivable by him under that lease or agreement in any later chargeable period with the substitution for the reference to one-half of a reference to the relevant fraction as so determined.