A cortosis mine was actively operated by the Jin'ha on the planet of Obredaan, primarily to refine cortosis ore, which they then used in the construction of their weaponry.
Just to the immediate right upon entering the mine was a landing platform where a dormant Jin'ha starship was parked. Two doorways opened into a spacious chamber containing numerous crates, a shallow depression filled with deadly fluid near the back, and a staircase leading upwards to an upper level. Multiple hallways branched out, eventually converging at an elevator shaft that allowed individuals to descend deeper into the complex. The cortosis refinery was situated within a sizable chamber at the mine's deepest level.
In the year 32 BBY, the Jedi Knights Qui-Gon Jinn and Obi-Wan Kenobi were dispatched to Obredaan by the Jedi Council. Their mission was to investigate the system following their success in prevented a conflict on Coruscant that was instigated by the criminal organization known as Black Heth, who at that time were receiving arms from the Jin'ha. Jinn began searching for the missing Masters who disappeared during a previous assignment, while Kenobi managed to sneak into the mine and later retrieved a cortosis metal sample.
The subsequent meeting between Obi-Wan, Jinn, and the rescued Masters resulted in spotting a Trade Federation gunship flying above them, which led the Jedi to suspect a connection between the Trade Federation and the Jin'ha.