British Aluminium Company Ltd essentially manufactured metal (6)
I believe the answer is:
cobalt
'metal' is the definition.
(I know that cobalt is a type of metal)
'british aluminium company ltd essentially manufactured' is the wordplay.
I cannot quite see how this works, but
'british' could be 'b' (abbreviation e.g. in 'BBC') and 'b' is found in the answer.
'aluminium' could be 'al' (Al is the chemical symbol for aluminium) and 'al' is found in the answer.
'company' could be 'co' (abbreviation) and 'co' is found in the answer.
A single letter 't' remains which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for cobalt that I've seen before include "Element 27; a deep blue" , "Ferromagnetic metal - shade of blue" , "Sort of blue" , "Silvery-white metal used in alloys" , "A deep-blue colour (6)" .)