It's that time of year when I can find some ice sheet on the top of buckets of water first thing in the morning. These can have two interesting structures. One is gas bubbles trapped in the ice and the second is ice daggers formed on the underside of the ice.
The formations get accentuated by placing the ice over some coloured card.
5Dmk2/MPE-65/430Ex flash. Focus stacked using zerene.