From the "I-wouldn't-drop-that-if-I-were-you" department:
Image: Dnn87 at en.wikipedia; cc-by-sa-3.0
That's a sample of 99.999% pure cesium... a whopping 1.36 kilograms of it, to be precise, stored in a massive ampoule in (I assume) mineral oil.
No, you definitely don't want to drop that. Just looking at that thing gives me the shivers.