Remains confused about origin of rock salts (8)
I believe the answer is:
mariners
'salts' is the definition.
('mariner' can be a synonym of 'salt')
'remains confused about origin of rock' is the wordplay.
'confused' indicates anagramming the letters.
'about' indicates putting letters inside.
'origin of' suggests taking the first letters.
The first letter of 'rock' is 'r'.
'remains' anagrammed gives 'mainers'.
'mainers' enclosing 'r' is 'MARINERS'.
(Other definitions for mariners that I've seen before include "Ratings" , "Sea-farers" , "Rinse arm (anag)" , "Seamen" , "Sailors" .)