| http://www.w3.org/ns/prov#value | - where Ln is a lanthanide mixture, natural or preferably unfinished concentrate, selected from a mixture of at least two, at least three, at least four, or at least five or more of La, Ce, Pr, Nd, Sm, and other lanthanides, with the proviso that if Ln comprises a mixture of only two lanthanides, the mixture is not the combination of La and Ce; La and Ce are selected from individual species of La an
|
