Old Number (British 591) Poss. Queen V. Cancel ?

Hi Everyone,
I have a few of these old stamps, with big number cancels on them, and I don't really know much about them. Does the cancel have a name for them? Any information would be greatly appreciated. Is there collectors of these specifically for the number cancels?

I also have a KH HK One Penny, purple Inland Revenue and a 48 cent Hong King up for trade with this one as well as I prefer foreign scenic, old trains, ships, BOB, mono, bi-color, not too picky, but prefer a MINT front, don't care about backside, okay with hinge / marks...

Thank you so much!
Sue
SueStamps
Here are the photos:

These are called 1844 type duplex postmarks although they lasted many years after that date.... and would be similar to this one. Your postmark is of the upright oval type (some would have been horizontal oval type).




Your number 591 indicates it was postmarked in Oldham in England.
edit... as to collectable ... yes... as many would collect their local town, city or county.

Hi.

I'm no expert on these (but there will be experts out there!) but the number cancels refer to the place the item was posted. All British post offices had a number. I Googled "591" and if this link is correct: http://gbstamp.co.uk/article/index-...ons-143.html then it means that this stamp was posted in Oldham, which is near Manchester in north-west England.

That link appears to have correct information. There's no secret about the numbers. Lists have been published. The "standard" reference is "British Post Office Numbers 1844-1906" by George Brumell
The numbers assigned to some post offices changed over time, but not in a major way.

A major thing to know:
England and Wales had numbers within an oval.
Scotland had numbers within a rectangle
Ireland had numbers within a diamond.