sphericity vs sphericalness

sphericity and sphericalness both are nouns.

Word	Noun	Adjective	Verb	Adverb
sphericity	Yes	No	No	No
sphericalness	Yes	No	No	No

As nouns, sphericity and sphericalness are synonyms defined as:

Other synonyms of sphericity include globosity, globularness, rotundity, rotundness.

sphericity (noun)	sphericalness (noun)
the roundness of a 3-dimensional object	the roundness of a 3-dimensional object