From Wikipedia: “An ice spike is an ice formation, often in the shape of an inverted icicle, that projects upwards from the surface of a body of frozen water. Ice spikes created by natural processes on the surface of small bodies of frozen water have been reported for many decades, although their occurrence is quite rare. … Natural ice spikes can grow into shapes other than a classic spike shape, and have been variously reported as ice candles, ice towers or ice vases as there is no standard nomenclature for these other forms.”