Rock and roll at labs (6)
I believe the answer is:
basalt
'rock' is the definition.
(basalt is a kind of rock)
'roll at labs' is the wordplay.
'roll' indicates anagramming the letters.
'at'+'labs'='atlabs'
'atlabs' is an anagram of 'BASALT'.
'and' acts as a link.
(Other definitions for basalt that I've seen before include "Type of rock is a blast, oddly" , "Rock containing olivine" , "Dark rock of volcanic origin" , "Commonest type of solidified lava; dense, dark grey and fine-grained" , "Common volcanic rock" .)