I had a similar idea in mind to your game's concept, but I think you executed yours well. The controls were responsive with jumps being a bit sluggish for me to miss the first jump a couple times in the game. Still, game feel was good after a bit of getting used to; I don't really play with mouse and keyboard. The idea of shining light on the gold is a great idea to help distinguish between real and fake, but even with the lamp, I was unable to tell which was fake, as all gold I shined gave off some particle effect that looked the same to me. Your use of sounds were nice though, the cave felt spooky to explore. As a suggestion, consider some sort of lamp light meter, similar to the Zombie FPS project from GameDev.tv, so that the lamp's use goes down each time it is pulled out, making it tougher to distinguish between the gold. Still, really great job here!