I am a chemist after all, so you must forgive me for the title....
This is a cluster of crystals of copper sulphate, that we made for chemistry school project few years ago. I still have them in a box. It is not really smart to touch them, but I have touched worse (I know how to stay safe :)).
I was trying to find something that is blue and natural, and besides few rare flowers and a sky I can't come up with much, at least in nature's area. There are a lot of blue things and colors around me but I am still very curious about this color and your choices...
