Gypsum and basalt are different (9)
I believe the answer is:
alabaster
'gypsum' is the definition.
(thesaurus)
'basalt are different' is the wordplay.
'different' indicates an anagram.
'basalt'+'are'='basaltare'
'basaltare' anagrammed gives 'ALABASTER'.
'and' is the link.
(Other definitions for alabaster that I've seen before include "Material for sculpting" , "Sculptors work with this" , "statue material" , "White translucent form of gypsum used for statues, vases etc" , "Arabs tale (anag.)" .)