Stalactites and Stalagmites
Stalactites and Stalagmites, , formations often found in limestone caves. Stalactites hang from a cave's ceiling and frequently resemble icicles, although some have a flatter, curtain-like appearance. Stalagmites are built up from the floor of a cave, almost always beneath a stalactite.
Stalactites are formed when water, containing dissolved minerals, drips from the ceiling of a cave. As each drop falls, it leaves behind a tiny bit of its dissolved minerals, usually calcium carbonate. These small deposits build up over thousands of years to form a stalactite. The drops of water falling to the floor of the cave leave more residue, which eventually forms a stalagmite. Since the drops spatter over a relatively wide area, stalagmites are usually thicker and have a greater variety of shapes than stalactites. If growth continues long enough, the two sometimes merge into a single column.