When I got to Jordan, I wanted to make ice. The place I was staying had a fridge/freezer but made weeny ice cubes. So, I switched to using a muffin tin (and they didn’t last long in the heat). But, when I froze the first ones, I had an “ice spike” on one of the cubes. Here’s a picture. if you would like to read more about ice spikes, start with the Wikipedia article.