I crushed 20 stacks of elementium ore two nights ago. I got 18 nightstones. Funny thing is, I had such bad luck with nightstones previously that I regularly had to buy one or two for the JC quest.
I also have accumulated nearly three stacks of amberwhatever (the yellow gem) but only one stack of the comparable orange gems from the crushing I've done in the past few weeks.
I am convinced that all of our experiences with this point to the existence of a scientifically provable formula which I will give the name: Retrograde Numerical Gestationalism. Also to be known as RNG or cynyck's Postulate. I don't know what a postulate is, but if mom were alive she'd be so proud of me right now!
One of my opinions is worth three of your facts.