From the back cover:
"A dead man's cryptic treasure map may lead to a fortune in Spanish gold -- or to a quick death. Can you elude Indians, claim jumpers, bandits, and vigilantes and find the lost gold of Mendoza?
Lost Conquistador Mine was originally used as a tournament module at the GEN C?ON XIII Game Convention. The module contains town and wilderness scenarios that can be combined to create a series of exciting adventures."