Part of brass section from Berlioz in concert (4)

I believe the answer is:
zinc
'part of brass' is the definition.
The definition and answer can be both substances as well as being singular nouns.
Maybe they are linked in a way I don't understand?
'section from berlioz in concert' is the wordplay.
'section' indicates a hidden word.
'ZINC' is hidden in the letters of 'from berlioz in concert'.
Can you help me to learn more?
(Other definitions for zinc that I've seen before include "Metal used for galvanising steel" , "Anti-corrosion agent" , "White metallic element, symbol Zn" , "Silvery-white metal" , "Metal alloyed with copper to make brass" .)
