Daniel,
yep, white and unsigned.
it's definitely from the same mould as the Afors bowl - do you know if any of the Afors moulds etc would have ended up at Kosta's factory ?
Interestingly I have another pair quite similar:
first picture is Afors graal, signed and normal production
second picture is unsigned, with added foot and ariel, but from same mould.
Gareth