Leaf one-piece mold and squeeze molds, circa 1910-1970s

One leaf one-piece mold and two squeeze molds used to make wax, plastic and paper casts for exhibits, possibly between the 1910s and 1970s.

One-piece molds are used by pressing or filling soft sculpting material in their shaped surface.

For leaf and flower reproduction a plaster mold, known as a "leaf cookie," was first made using fresh specimen while on the field.The leaf or petal was laid face up on a surface of clay. The clay was bedded up beneath and around to support the leaf in its natural position, and plaster of Paris mixed and poured over it to record the details. Layers would be added to build up the thickness and strength of the mold. When the plaster set, the leaf or petal would be removed, and the extra plaster trimmed away around the impression. The molds, after being dried and immersed 20 minutes in hot paraffin, were ready for use to make wax impressions. 

Squeeze molds are sets of concave and convex molds. Concave molds are forms that work just like other molds in that the molding material is draped over their surface. With concave molds, the inside surface is exposed, while the outer face is in contact with the mold. This is opposite to that of convex molds, in which the mold is in contact with the interior side. These sets were attached to clamps for leaf-making.

To produce plastic leaves, a plastic sheet was put between the molds, and then clamped tightly under very hot water so that it could take the impression of the leaf. For wax leaves, after placing a thin sheet of cotton and wire for the leaf stem over the top of the mold, molten wax was poured over the cotton and then the squeeze molds were pressed over the hot wax. The wax was then cooled, and once the mold was removed the replica was ready for assembly.