Need Little Help With Two GB Stamps

Can't find this baby anywhere in Scott or SG.



Doesn't look like stationary because it affixed to the paper and tight with the cancel. Doesn't look like a revenue too, has postal cancel. My guess it is not mother England, but some colony.However quick search for Cardiff brings me to Wale's.


This other one is not that much exciting, but still quite interesting to me, especially the cancel, or whatever it overprinted with.

The first one looks to me like someone cut a piece off some stationery, and glued it to another envelope.

Would such thing be accepted by post office? Wonder what was written next to the stamp.

This was valid use at the date of the postmark.

Unused cut-outs from postal stationery could be used like this until 1870 and then again from 1905.

Something new every time. Who would've thought.
Still a very lovely piece.