This is a small (1/8" inside diameter) vial of liquid xenon. It takes quite a lot of pressure to turn xenon gas into a liquid, so the vial is made of high-strength quartz glass, and it's embedded in a large cylinder of acrylic to contain the gas if the glass were to break. Hopefully the acrylic would be strong enough.
Actually there is only liquid in the ampule below 16C (61F), so at room temperature it's just gas. Fortunately it's winter now so I could easily cool my studio down to about 50F to photograph the 360 degree rotation I make of every new sample. This process takes half an hour (360 frames shot one every 5 seconds as the sample makes one complete revolution in 30 minutes). I put the sample in the freezer for a few hours, which got it about half full of liquid. You can see it evaporating slowly until only about a fifth of the ampule is liquid by the end of the rotation. (The rotation is shot very close up so all you see is the bit of liquid at the bottom of the vial.)
Source: Ivan Timokhin
Contributor: Ivan Timokhin
Acquired: 28 December, 2006
Text Updated: 7 January, 2007