Fossil Fever

CASTING & MOLDING A cast is essentially a copy of a bone.   Sometimes it is called a replica.   The advantages of a cast are that it is lighter and stronger than real bone.  It retains all of the external details of the original specimens.    A two part mold can be made from an original fossil.  The bone is supported with clay and building blocks. More clay is used to cover about half of the original fossil.          Once the molding rubber has completely dried, the sides made  of building blocks are removed. After they are removed, the top portion (molding rubber and the original fossil)  can be separated from the clay.    Now the other side needs to be molded.  The first part that was molded is now placed on the bottom and the walls are built with building blocks to be high enough to cover the fossil and have s