First they found the diamonds, Solomon's men. A diamond mine of incredible bounty. Then they built the city around the mine, so that it should be protected.
18 seconds sound clip from the Congo (1995) movie soundboard.
You can hear this line at 01:12:05.900 in the Blu-ray version of the movie.
Quote context
[...]
- Jeez.
- It is the city of Zinj that I have looked for all my life.
- See? The eyes. It is the same.
- Kahega, guns up. Stay alert.
- Come here, Amy. Stay with me.
- The savagery of the guards was a legend. They instantly fell upon any thief, any transgressor.
- And the diamonds flowed to the kingdom of Solomon.
- Well, what happened? Why did the city die?
- No! No! The diamonds are here!
[...]