Harriet was inspired by an artist who made plaster ‘prints’ from people’s wedding bouquets. She wanted however to make a ceramic version rather than plaster, to enable her to make not only flat plaques but also cylinders and other forms.
The first stage was to roll a very flat smooth sheet of clay and impress various plants (clay sheet seen in image on the left). Before this could dry Harriet cast it in plaster by building up a clay wall around the edge of the sheet and pouring in the plaster. However she realised that when she rolled a sheet of clay onto this plaster ‘positive’ mould of the plant forms it would produce a clay ‘negative’ (or imprint). She wanted the plants to be in relief (sticking out or ‘positive’) in clay so I helped her make (1) an alginate mould from the clay sheet, from which (2)a plaster negative could be made, onto which (3) the clay could be rolled resulting in a clay positive! If you’re confused then don’t worry, it often takes the making of something like this before the various changes from positive to negative are completely understood!
Alginate is a flexible one-off moulding material that sets very fast and is perfect for work like this where the level of detail is high. In this case flexible alginate rather than plaster had to be used for the intermediate stage (stage 2 above) of casting as there were undercuts present. A plaster negative (stage 3 above) would have simply got stuck to a plaster positive (stage 2).
The resulting casts in porcelain were beautiful, delicate and detailed (images to follow).
If all this intrigues you then why not join the class and learn more about mould-making!