A mold fossil (or fossil mold) is simply this: A living organism such as a plant, seed, fish or mammal, dies and is buried in a sediment of sand, silt or clay. The organism decomposes, but leaves a mold (a negative) of itself. Thus a mold is a faithful representation of the living organism.
Instructions
1. Present the mold fossil as is. Instruct your students that a mold fossil is superior to a fossilized bone, because a mold fossil represents the organism in its living form. A fossilized bone represents a dead organism. A mold fossil also captures plants like ferns, which were delicate and rotted away before they could petrify.
2. Create an alginate cast from the mold fossil. Mix dental alginate per the manufacturer's instructions, and spread it in a thick layer within the mold. Allow to harden per manufacturer's instructions. In minutes, you should have a perfect (albeit purple) representation of the living organism.
3. Create a wax model from the mold fossil. Simple beeswax melted in a pot will serve. Spread the wax in the mold, overflowing it, and allow to harden. Carefully loosen the mold fossil, for a perfect representation of the organism. Such a cast is not durable, but is useful for classroom demonstrations.
4. Create a metal cast from the mold fossil. First, create an alginate or wax cast cast as per Step 2 or 3. Mix Plaster of Paris per manufacturer's instructions, and press the cast into the plaster. Wait one hour for the plaster mold to harden, and remove the cast. Bake the plaster as per manufacturer's instructions (typically 150 to 200 degrees Fahrenheit, for 45 minutes). Melt pewter, lead or bronze in a melting pot, and pour into the plaster mold. You should have a durable cast of your mold fossil.
Related posts
Create your own fossils with plaster.Fossils fall into two main categories: mold and cast. A mold is the imprint of an object--often shells but sometimes bones or plant matter. When sediment fills...
Making foot and hand imprints is a classic project for kids and adult artists. Children's footprints are often painted with bright colors and used to make gifts such as tree ornaments and paperwei...
Make castle models with castle block molds.Building castles is a hobby that both adults and children can enjoy. You can make castles as simple or as complex as you want, it just takes a little cre...
Make a custom non-toxic plaster mold to use in your clay, soap making or wax crafts. You can use nearly any solid object or a dry clay sculpture to form your mold using plaster of Paris, which is...
Gyprock makes plaster products that can have porous and non-porous surfaces.Gyprock is a name brand of plasterboard and plaster products that are used in the home to create ceilings and walls. The...
