epoci

Hey, I'm using Voltz through tekkit launcher and noticed that Lapis Lazuli and Emerald ores are missing from my game world, they're there in creation and using cheat mode, but I was not able to find any in my world of playing it for over a week now. I'm using the developed build and have tried clearing cache already. Have anyone encountered a similar problem or has an idea why this might be? Thanks for you help