Small Circle Stamped On The Back Of My Seahorse

Thank you all for your very helpful input! This is great -- so glad I joined the forums! (I have accumulated many many questions haha)

littleriverphil: I've been examining this stamp very closely as you suggested, and I do think there's something odd about it. Comparing it against others of this issue (and specifically against a mint copy of the same denomination), the end of the nose strikes me as... somewhat deformed looking? Ski-jumpish? I'm pretty sure you can spot it on the image above, but if not I will upload a tighter shot. The others don't have this odd nose. I think there are some other differences as well but my eyes are tired of looking at them. LOL

scotzm: are there specifics about those 18 plates somewhere? Presumably they had differences amongst them that might at least give me more info about the varieties I seem to have.

CanadaStamp: Yes, I've sadly discovered that in my mom's collection as well. Not her hand-writing, so I have to assume she got them elsewhere unknowingly. Even more annoying (to me), the majority of id numbers on the back (in black ink of course) are wrong! Ugh!

"are there specifics about those 18 plates somewhere? Presumably they had differences amongst them that might at least give me more info about the varieties I seem to have."

It is a very complicated series if you involve all the shades etc.
Waterlow used two plates... De La Rue used the two Waterlow plates plus three of their own... and Bradbury, Wilkinson used a different type of plate with five plates giving stamps 23mm high and thirteen plates being 22.75mm. Many of the actual printings can be found by study of the perforation types, stamp sizes etc but plating might be tricky. The only source I know is this book which would probably cost an arm and a leg...

Holy smokes! I had no idea! Thank you for the information scotzm... and I must be losing my mind, because now I'm sitting here contemplating whether I should try to find that book -- ha! Not because of this one stamp, though. At a glance, I have 11 seahorses (counting the 1922 Irish overstamps), which seems like a pretty decent headstart on a sub-collection and area to focus on for me maybe. Sounds silly, perhaps, but having spent a year immersed in my mother's collection, I'm starting to be excited about the idea of developing my own areas of interest.

:)