What lurks in geodes?

Celestite -- a strontium sulfate mineral. I've had this geode since time immemorial -- I think I got it on a trip to Nevada/Arizona in 1971. But it didn't occur to me until now, when reading up on celestite for other reasons, that I actually had some growing in it. The crystals are not the hexagonal or triclinic or quartz growth or calcite, but faintly blue, sometimes more prisamatic. It makes sense, as there's plenty of Sr (a fairly mobile element with no where else to go) and S in the volatiles that fill gas pockets and host lavas in which the geodes form. So, I feel quite happy knowing there's a new "rock baby" in my collection that I didn't even know I had.