In addition to what is provided below:

(a) The general definitions, abbreviations, and methods of analysis set forth in 40 CFR part 401 shall apply to this subpart.

(b) The term rare earth metals refers to the elements scandium, yttrium, and lanthanum to lutetium, inclusive.

(c) The term mischmetal refers to a rare earth metal alloy comprised of the natural mixture of rare earths to about 94-99 percent. The balance of tha alloy includes traces of other elements and one to two percent iron.