Mixing tin with special trademarked material (10)
I believe the answer is:
plasticine
'trademarked material' is the definition.
I can't tell whether this definition defines the answer.
'mixing tin with special' is the wordplay.
'mixing' indicates anagramming the letters.
'with' is a charade indicator (letters next to each other).
'tin' put after 'special' is 'specialtin'.
'specialtin' anagrammed gives 'PLASTICINE'.
Can you help me to learn more?
(Other definitions for plasticine that I've seen before include "substance used by modellers" , "Modelling clay" .)