Crossword Genius

Metal cask German sent abroad (8)

Ross

I believe the answer is:

tungsten

'metal' is the definition.
(tungsten is a kind of metal)

'cask german sent abroad' is the wordplay.
'cask' becomes 'tun' (tun is a kind of cask).
'german' becomes 'g' (abbreviation).
'abroad' indicates an anagram.
'sent' is an anagram of 'sten'.
'tun'+'g'+'sten'='TUNGSTEN'

(Other definitions for tungsten that I've seen before include "Metallic element used for lamp filaments" , "Element used in steels" , "Hard malleable metal" , "Lamp filament metal" , "Rare metallic element" .)

I've seen this clue in The Guardian.
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