Greenstone is a large open pit gold mine in the Geraldton-Beardmore district of western Ontario, Canada. The property is located approximately 275 km northeast of the city of Thunder Bay and approximately 4 km south of the town of Geraldton.

An updated Technical Report was released in October 2024 outlining a 15-year mine life (from 2025 on) producing an average of 332,000 ounces of gold per year.