This eyedropper pen is said to be a Blackbird. It has a Blackbird nib but I have never seen a Blackbird with such a large step from the barrel to the slender section. Also it has no imprint of any kind despite being in unworn condition. I’m unaware of any Mabie Todd pen without a barrel imprint. What do you think?
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I bought a Blackbird with an Onoto de la rue nib inherent. Could it be a Blackbird nib replaced into a different make? Not as knowledgeable in fountain pens as yourself, so it’s all I can offer. All the best.
That’s very likely.
The good news is that you got yourself a Blackbird nib… The rest is random
It isn’t mine, but the owner will have the Blackbird nib, as you say. It’s nice material but it isn’t a Blackbird!