The first metal casting becomes what is called the "master". Ideally the master is kept forever as a way to go back and make a new mold or alteration of the design. The rod attached to it is called a sprue which served as a channel for the molten metal to flow through during the casting process.
The casting success of the master is crucial. It is called the "lost wax casting process" because the wax is truly lost in the burnout stage. If the first casting is not successful, many days or weeks worth of work, carving the design model can be lost. Any flaws in the master will be reproduced in each piece made from it.
This photo shows the master casting after I have refined and polished it. It is ready for a rubber mold to be made of it.