Forest contains raw materials (4)

I believe the answer is:

ores

'raw materials' is the definition.
(I've seen this in another clue)

'forest contains' is the wordplay.
'contains' indicates the answer is hidden within the clue.
'ORES' can be found hidden inside 'forest'.

(Other definitions for ores that I've seen before include "Bauxite, haematite etc" , "Mined minerals" , "Mineral deposits" , "Metal-bearing minerals" , "Sources of metal" .)

I've seen this clue in The Mirror.

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