The Toltec crystal skull, surrounded by Guardian Statues.
The Toltec Crystal Skull was an artifact hidden in a temple near Lucasio, Mexico.
Indiana Jones recovered the the skull in the course of his adventures in Mexico in the 1930s.
Shady collector Victor Van Loon attempted to obtain the artifact for himself, yet Jones was able to solve the temple's puzzles faster, defeat the ancient guardians, and take the skull to safety.