Read this in my teens (mid '80s), it was a scifi novel.
Can't remember a huge amount about it, but the main character, something happens where he ends up thrown into a slave mine, and has to survive, build friendships, work his way up, and eventually discovers an alien artifact (the reason for the mines), which he smuggles out, and later discovers these artifacts are how all spaceships are secretly powered.
Written in English, but that's about all I can remember
Any help appreciated, thanks
Can't remember a huge amount about it, but the main character, something happens where he ends up thrown into a slave mine, and has to survive, build friendships, work his way up, and eventually discovers an alien artifact (the reason for the mines), which he smuggles out, and later discovers these artifacts are how all spaceships are secretly powered.
Written in English, but that's about all I can remember
Any help appreciated, thanks