Strange brick-carrier I included made of a hard metal (7)
I believe the answer is:
rhodium
'a hard metal' is the definition.
(I've seen this before)
'strange brick-carrier i included' is the wordplay.
'strange' becomes 'rum' (I've seen this before).
'brick carrier' becomes 'hod' (I've seen this before).
'included' indicates putting letters inside.
'hod'+'i'='hodi'
'rum' going around 'hodi' is 'RHODIUM'.
'made of' is the link.
(Other definitions for rhodium that I've seen before include "Metallic element, atomic no 45" , "Hard metal" , "Hard metallic element" , "Chemical element, symbol Rh" .)