These experimental vases were made around 1930, the numbers next to the mark under the vases are codes for the paint and/or glazes used. Herman Verlee (who was in charge of the laboratory) provided the paint and glaze. Willem Muller was the dedicated painter. Because the work was rather specialised I do not think any other people became involved.
Decor: Unique Year: around 1930. High:
9.5cm. Wide: 9cm Painted by M = Willem Muller.
Decor: Unique Year: around
1930. High: 14cm. Wide:
13cm Painted by: Unmarked, but likely by Willem Muller