A type of dripstone formation where the deposits hang from the ceiling of the cave is called a stalactite. Stalactites are formed when water containing minerals, such as calcium carbonate, drips from the ceiling of a cave. Over time, the water evaporates, leaving behind mineral deposits that build up and form a long, icicle-like structure hanging from the ceiling. Stalactites can vary in size and shape, and they are often found in caves with dripping or seeping water. They can take thousands of years to form, as the mineral-rich water slowly deposits minerals layer by layer.