Assertion: metal's form | /r/HasProperty | variation
Facets:
value: on the theme of chemical periodicity
type: OTHER
value: in its absence
type: OTHER
Source sentences:
text: In its absence, the many different forms of periodic table can be regarded as variations on the theme of chemical periodicity, each of which explores and emphasizes different aspects, properties, perspectives and relationships of and among the elements.[n 16]