Stalactite and Stalagmite
- The solution of water containing limestone seeps through the roof of caverns in the form of a continuous chain of drops.
- A portion of the drop hangs on from the roof and on evaporation of water, a small deposit of limestone is left behind contributing to the formation of a stalactite, growing downwards from the roof.
- The remaining portion of the drop falls to the floor of the cavern.
- This also evaporates, leaving behind a small deposit of limestone aiding the formation of a stalagmite, thicker and flatter, rising upwards from the floor.
- Sometimes, stalactite and stalagmite join together to form a complete pillar.
Tufa
- Tufa is a variety of limestone formed when carbonate minerals precipitate out of ambient temperature water.