New Age element (4)
I believe the answer is:
neon
'element' is the definition.
(neon is a kind of element)
'new age' is the wordplay.
'new' becomes 'n'.
'age' becomes 'eon' (I've seen this before).
'n'+'eon'='NEON'
(Other definitions for neon that I've seen before include "Noble gas used in illuminated signs" , "Brightly coloured advertising sign" , "'Chemical element, often used in lights (4)'" , "Small plant; colour" , "One of the six inert gasses" .)