A crystal that changes colour when rain is approaching?

Question

When i was about 2 years old, my grandmother gave me this rock/cystal carved into the shape of a dog. It was a crystal that changes colour when rain is approaching. It was pink, but when the rain was comming, usually a day before, it changed to a dark purple. I loved it so much, I broke it in two to look at what was inside. I was trying to see what made it work. It was white/pink inside, but it was a solid rock or crystal. Does anyone know what that was or have had one of these?

Answer 1

Perhaps Cobalt (II) Chloride (CoCl2), although its color behavior is the reverse of your description.  On dry, low humidity days, it is blue; on wet, humid days, it is dark red.

Answer 2

They are painted with something that reacts to humidity in the air :)