Never seen this one before, so the bump really helps.
The combination opal inner clear outer was widely used by Meijdam in Leerdam in the 1950s and 1960s and I would not be surprised if your vase turned out to be one of these. I bought a bottle vase in the same colour combination 2 weeks ago and discovered it was signed. The sig is so light that it requires talent and magnification to spot it.