Final answer:
The lost-wax casting method requires the destruction of the mold to retrieve the hardened metal sculpture, resulting in unique or limited edition pieces.
Step-by-step explanation:
The mold that was broken and is now only used for limited edition models refers to the process of the lost-wax casting method. In this technique, a clay mold is created around a wax model which is then melted away.
When the metal has cooled and hardened inside the mold, the mold must be destroyed to remove the metal sculpture. This technique lends itself to the production of one-of-a-kind sculptures or limited editions because the mold's destruction means it cannot be used again.
An example of a sculpture created with this method is the Chimera of Arezzo, a notable work suspected to be from the Etruscan civilization though debated due to its uniqueness.