I managed to make a stable dense ore age by purposefully adding in instability and a bit of luck. If you add into your age charged and scorched earth you can greatly reduce the chance of getting meteors, spontaneous explosions and decay. Just make sure you have all the required symbols + those two instabilities.
Has anyone been able to successfully make a Mystcraft Dense Ore world that's quarry compatible? I'm currently working on my Fusion Reactor which calls for about a stack of Iridium Plates.
So if anyone has a set up that works I'd really like to hear it.