I've been musing on and off about WMF pieces for a while and this vase.
I posted a link to a display of WMF pieces that had a vase in with a crimped rim (different decor to Steven's vase) and was apparently 1948
http://www.zeller.de/de/katalog/auktion-95-dez-07/auktionsartikel/ikora-schale-11/Ivo made a comment on another thread about WMF doing straight rims. I also cannot find a single piece in the Book (Burschel and Scheiffele) that has any crimped rim. The vase I linked to is apparently 1948 but there doesn't seem to be a 1948 reference in the book though.
And according to the book Ikora-Medusa was lemon yellow which Sue's vase is but Steven's isn't.
I don't know if they did another design that only had one colour and the bubble crackle effect in the same way the Medusa does, I can't find one.
I'm not entirely sure that this fan vase is WMF Ikora is what I'm trying to say

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