Dear VIPEr colleagues,

A colleague of mine gave a presentation at the Virginia Association of Science Teachers last weekend. After his talk, one of the audience members asked him if he could help him identify something that he found at his school that is apparently a demo. I've attached the picture of the tube. It contains what appears to be mercury (liquid, silver, metallic looking) and a blue solid. The sample doesn't react heat (60 deg C), cold (0 deg C), or UV light. 

Do any of you have any idea what the blue material might be and/or anything about this demonstration (assuming it is a demo, that is)? I'd love to be able to report back on what this is.

Thanks! Fingers crossed that the collective wisdom on VIPEr can solve this mystery.