Raw material from forest (3)
I believe the answer is:
ore
'raw material' is the definition.
(I've seen this before)
'from forest' is the wordplay.
'from' indicates a hidden word.
'ORE' can be found hidden inside 'forest'.
(Other definitions for ore that I've seen before include "Small coins" , "foreign money" , "coinage" , "Mined material" , "Raw mineral" .)