My mom bought me this snazzy little silicon ice cube tray (ice flower tray, actually) from IKEA when she was up here, and I finally got around to filling it with water a few days ago. Today I opened the freezer to get something else, and got a strange little surprise from my ice cube tray:

Ice spikes! I don’t know about you guys, but I pretty much never make/use ice cubes, so this was a new phenomenon to me. So I thought, “hey, water’s weirder than hell, this probably has something to do with its special freezing properties.”*
So I Googled “Ice spikes” and what do you know—that’s actually what they’re called. Usually they’re a lot bigger and more impressive, but conditions in which they form are usually more favorable than “Claudia’s freezer.”

They form when conditions are just below freezing and arise due to a fact we all know: water expands when it freezes. When conditions are appropriate, a thin layer of ice can forms over the surface of the water. However, if the integrity of the ice layer is compromised in a certain place, the water beneath it, still in the process of freezing, can be forced up through the opening in the upper ice layer as it continues to expand. This can also happen if there’s a bubble trapped in the water.

Me being me, I’d like to see a comparison of the average size of ice spikes formed in ice cube trays made of non-expandable material (hard plastics) versus those formed in ice cube trays made of more flexible (and possibly expandable?) material like silicon.

Yeah.

*This thought was shortly followed by, “SCIENCE BLOG!”

Today’s song: UPular by Pogo