Fossil Molds and Replicas

Welcome to a new way of teaching about the past

Fossils have always fascinated us. They are particularly interesting to children. They love to look for them in their backyards, out in the wilderness and even at Grandma's house. The smallest curiously- shaped rock becomes a great treasure. With that in mind we have developed a hands-on kit to further their interest in the classroom.

Paleontologist Karen Cloward has molded several original fossils from her collection, and offers these molds for creating fossil replicas. The children will enjoy selecting their mold, mixing the plaster and pouring it into the mold. They can watch the plaster set and after it has cured they can remove the fossil cast and paint it.

Some unique features of our molds:

• Real fossils are used to create each mold

• Molds lay flat on the table for easy use by children

• Molds won't spill or tip over

• Molds are large enough to see good detail of the fossil

• Fossils are set in 'matrix' so they look like they are coming right out of the ground

• Molds are made of silicone rubber, not latex- a known allergen

• Molds will last for years, good for pouring lots of casts

• Plaster casts come out of molds easily, no release chemical necessary

• Molds can be washed in water for easy cleanup when necessary

Why use fossil molds in teaching:

• Children use decision making skills in choosing which mold to use

• Gross motor skills are used in the mixing and pouring

• Requires hand/ eye coordination

• Fine motor skills are used for painting

• Creativity is developed as they choose and mix colors to paint their perfect cast fossil

• Geology, Art, Chemistry and Physics can be demonstrated through the casting process

Kits contain the following:

4 molds, 5 pounds plaster (enough for 25-30 casts), 4 paints, 12 paint brushes, instruction sheet

About the Owner:

Karen Cloward has been an active paleontologist for the past 19 years. She has co-authored several scientific papers and has named 2 new species of dinosaurs and 1 new species of pterosaur. She was on the design team for the Museum of Ancient Life at Thanksgiving Point and the Director of Education and Exhibits. She is currently preparing dinosaurs for a traveling exhibit, and museums around the world.

How Fossils Are Dated And Indexed

Geologic periods can be determined or identified using the different fossils found in the sediments. However, in order for an organism to become a fossil a couple of things have to happen. The organism needs to die in or near water and then be buried rapidly. This preserves the specimen in the best possible way. Since igneous rock (rock formed from cooled magma), and metamorphic rock (rock that is changed by intense pressure and heat) do not hold any fossils, they are not the type of rock in which to look for fossils. Fossils are only found in sedimentary rock. Sedimentary rock is laid down in layers caused by wind, erosion, rain and bodies of water moving particles of minerals and depositing them one after another in what becomes large sheets of deposits. Trapped in these deposits are the organisms themselves that become the fossils we seek today. So how do these organisms tell us the age of the sediments in which they are found?

Paleontologists really like species that existed for short periods of time as they give us an indication of the age of the sediments they are found in. An organism that existed for no more than say a few hundred thousand years, and is found all around the world, indicates that the sediments it was found in are the same age even though the sediments may look very different. Sediments can be laid down under very different conditions throughout the world but the species itself is the same, so the different locations and sediments must be the same age. These types of species are referred to as index fossils or guide fossils. Since sedimentary rock is laid down a layer at a time, we can surmise that the top layer is the newest and the bottom layer is the oldest. There have been lots of movements in the earth's crust with upthrusts, down thrusts, plates shifting, etc., but a careful study of the layering can give us a pretty good idea of what is older and what is newer. We call this comparative or relative dating. So a fossil found all around the world that is lower in the layers of rock than those above it is considered older and indicates that the rock it was found in is older too. By observing and recording enough layers and the specimens found in each, you see the progression of the fossil record.