Author wants this chair carved in stone (6,8)
I believe the answer is:
agatha christie
'author' is the definition.
(mystery novelist)
'this chair carved in stone' is the wordplay.
'carved' is an anagram indicator.
'in' indicates putting letters inside.
'stone' becomes 'agate' (agate is a type of stone).
'this'+'chair'='thischair'
'thischair' is an anagram of 'hachristi'.
'hachristi' placed into 'agate' is 'AGATHA CHRISTIE'.
'wants' acts as a link.
(Other definitions for agatha christie that I've seen before include "Detective story writer" , "author" , "One who wrote" , "[THE QUEEN OF CRIME] - with 16d" .)