Depositional Features

In the open air of the cave, some of the water may evaporate from the carbonate rich solution and increases the concentration of dissolved bicarbonate.  Eventually, it becomes saturated and carbonate begins to precipitate. Alternately, the CO2 dissolved in water can come out of solution increasing the pH of water. Either or both of these processes cause previously disolved carbonates to precipitate on surfaces and to build up limestone deposits. The material deposited by ground water is called travertine or more informally, dripstone.  Cave features or formations that are formed from dripstone accumulations are called speleothems that may grow as much as 1 cm/year under favorable conditions.

If the water in the pools is constantly agitated, as from drips, cave pearls begin to form as carbonates precipitate on limestone particles in the pool, which act as seed grains. The constant motion of the water in the pool prevents the "pearl" from attaching to the sides of the pool but not from growing as additional travertine layers are added to its surface by precipitation.

They are as varied and unique in their expression as caves are. Some of the more common speleothems are: