The museum was busy Saturday, full of people learning about casting. Alton Dooley and Raymond Vodden, from the Paleontology Department at the Virginia Museum of Natural History have been working with students in the museum for the past 2-3 weeks casting our giant beaver (Castoroides ohioensis).
On Saturday they brought the cast making process up a level into the museum. Students gave demonstrations on some of the most exciting final steps in the process of making a cast. We mixed the resin, which starts as a clear brown liquid and hardens into a solid plastic. Then poured it into the silicone molds where we watched it transform, becoming solid, opaque, and white. The transformation began at the center where the white spiraled in on itself and out to the sides. Once they were set and had become a hard plastic all the way through we were able to remove the casts and paint them to look like the original bone.
In addition to casting bones from the giant beaver we casted other species like teeth from a giant sloth, a prehistoric horse, and a baby mastodon. Museum goers could buy them to take home as a souvenir. Once all the bones have been cast they repair any defects, like air bubbles, and paint them to as close to the originals as possible. After this the skeleton will still have to be assembled for display. The casting of the giant beaver will allow other museums to display a copy of our specimen so that even more people can see and learn about the giant beaver.