Which preposition to use with spheroids

at Occurrences 1%

If Thomas Roch is to be credited, this fulgurator could shatter the terrestrial spheroid at one blow.

of Occurrences 1%

He wears the usual youth's garment, the short toga, reaching below the knee, and a hollow spheroid of gold suspended round his neck.

on Occurrences 1%

" He replaced the spheroid on the table.

Which preposition to use with  spheroids