Great Britain #173 Or #179

I think this is a #173 A91, however they state there is a reprint but its olive brown I dont this this is olive brown it also states it usally has a dot in center top I cant see one

Lastly, it says that reprints are 22 3/4 mm and original are 22mm
but I don't know where to measure a stamp from? this is my first need to measure

if its original lists at $190, reprint $75

Stamps are measured mostly by the frame lines, not the actual outside edge of the paper. The brown line printed part.

I do not know the answer to the first part.
Try searching online or ebay to see if anyone has either or both listed.

Thanks puzzler, today was day one with this device... I dont really know how to use it yet I was planning on a websearch and start reading about them and avoid bugging everyone on here with such a trivial thing.

Oh, not trivial at all, at all.

One of the important tools of philately and stamp collecting.

And it is easy to mis-measure too, especially when the stated measurements are very close. You see what you want to see sometimes. On one issue in Canada anyway there is even a note in the catalogue about this.

By the way, second time around, after paying too much attention to the cancel on the stamp (I like cancels) I notice that you cunningly overlaid the perf gauge over the stamp. Cancel blindness that would be called perhaps? Looks like 22-3/4 mm to me, outside frame line to outside frame line.

I found it helpful to have both types of a cheaper stamp that has measurements like this (Newfoundland KGVI issues) and measure away until I figured out what 'they' were measuring.

Practicing with the real thing is best, but sometimes not possible of course.

I see what your saying its 22 mm, from the inside line and 22 3/4 from the outside line... I just don't know which one...

When they say 'measure the stamp, they are saying 'measure the printed portion of the stamp, all of it.'. If you just measure between the inside lines you are missing part of the design of the stamp.

Just imagine a black piece of paper and then everything else on that piece of paper , excluding the holes punched in (perfs), will be 'the stamp'.

Stanley Gibbons catalogue just shows the printed portion of the stamp in their concise edition. They do not show the perfs at all.

from Gibbons 2005 Great Britain Concise Catalogue

Thanks for your help, I understand now what to measure by seeing that.