question
Two vases with the same model and with a glaze that is used by van Woerden. The left vase is 5 cm smaller.

Note: Because the one type of clay shrinks more than the other, there may be a small difference. However no 5 cm.

answer Hugo and Marius
It may be that there are two different sizes. However, this is very unlikely, because we had known that.

When casting with the same clay vases are always the same size. When turning by hand one vase could be larger than the other.

If it is turned by hand, you can see a hand spiral on the inside and bottom.

If the vase is casted you can see inside some accumulated of clay on the bottom, just as the left-over in an empty yogurt bottle.

note
IYou can seen on the right photo below a van Woerden vase that is turned by hand. At the left the vase is inside smooth. So not be hand turned, but casted.

An other possibility. Mr. De Jong from the Raam, who once was our salesman, has together with Montagne from Nieuwkoop planned a kind of robbery. They had exactly copied our products. Especially the alkaline copper blue glazes.

On the photo right you can see a clear mould line. So the blue vase is casted.

OK then the unusual shape of the K40 is a casted imitation who was manufactured only for short time (like other forms of us) by the factory of Hans Montagne. His factory was located in Nieuwkoop under the name "Gemovers". He is gone bankrupt and we have acquired the factory about 2 years ago. Currently, we are automate the factory.

note
On facebook is a public group "West German Pottery (and East German Pottery)". Because Vest Keramiek have Fat Lava glazes, they posted also Vest vases.
An orange vase, which exactly resembles the blue-green of Gemovers, was identified as Vest.
Vest has never used orange glazes. The orange vase is also made by "Gemovers" at Nieuwkoop.
Source photos: Facebook group "West German Pottery (and East German Pottery)"