130R170. Where more than one property of a taxpayer is described in Class 28 in Schedule B and some or all of the properties, referred to in this section as “multiple mine properties”, were acquired for the purpose of gaining or producing income from particular mines and not from any other mine, a separate class is prescribed for the multiple mine properties that(a) were acquired for the purpose of gaining or producing income from the particular mines; and
(b) would otherwise be included in Class 28 in that schedule.