The pyramid-shaped ice formation you see here growing from a bird bath in England is a natural variation on a phenomenon known as "ice spikes." Most spikes are thin lances growing from ice cube trays and, occasionally, small ponds. Ice pyramids are more rare - and harder to form.
This is amazing. In a little over a minute, you can watch a water droplet on a plate cooled by liquid nitrogen grow first a spike, and then a tiny little forest of ice. The forest spreads across the top of the droplet and grows down the sides. We'll tell you why.