France: Colonies 20c Blue, With Lille Postmark

The stamps seems to be a Colonies issue. Not a great copy, obviously! However, I am intrigued by the postmark (2046), which I understand to be for Lille.
Can anyone enlighten me as to whether this is unusual?
Many thanks.

It is a trimmed French stamp not a Colonial issue,

Pagoda

It's a beautiful cancel, isn't it? Nothing unusual about it, though.

Just to be clear - my interest is in the fact of a Colonies issue being used in Lille - not the mark itself.

Unfortunately, as Pagoda states above, it is a France stamp, not a Colonial issue stamp.

Thanks all!

There are traces of perfs at the top and bottom

Hmmm - I agree it's a French stamp, sc 57. Both quality of printing and postmarks are clear indicators. And as stated, remains from perfs are visible top and bottom. What is making me wonder is the full margin including indication of the frame of the next stamp on right side - without any perfs seperating them. (?) Is it simply a very poorly centred perf stamp that has been trimmed to make it look like a full imperf margin on right side? Or could it have been part of a horiz imperf pair (but no such item is listed in my cat at least...)

Canary - very nice SON postmark - sorry for the condition