(1) For the purposes of relief under this Part, income from the sale of goods shall not include income from -
(a) any mining operations for the purpose of obtaining, whether by underground or surface working, any scheduled mineral, mineral compound or mineral substance (within the meaning of section 2 of the Minerals Development Act, 1940), or
(b) any construction operations (within the meaning of Chapter 2 of Part 18).
(2) Where a company carries on a trade which consists of or includes the manufacture of goods and -
(a) in the course of the trade, it carries on any mining operations (within the meaning of subsection (1)(a)) from which it obtains any scheduled mineral, mineral compound or mineral substance of the kind referred to in that subsection, and
(b) any such mineral, mineral compound or mineral substance is not sold by the company in the course of the trade but forms the whole or part of the materials used in the manufacture of such goods or is to any extent incorporated