Lumen, for 25 A, the definition is 'cleaning'. There's the usual 'five' and the usual 'silver', with a two-word phrase meaning 'admitted' put inside the latter.
36. A 'hidden' answer, with 'spinning' indicating....
'Movement' is the definition.
That's what held me up, Lumen! I got the Quebec part from Chambers, not expecting it to be there … and it was. I guess I didn't know as many abbreviations as I thought I did! The rest of the clue answer was easier - the usual 'advanced', a logical 'natural'.