Deposition by Groundwater

Have you ever seen a cave filled with stunning rock formations? These natural structures form when groundwater carries dissolved minerals and deposits them over time.

Limestone caves are the best places to see these formations. As groundwater flows through the cave, it leaves behind a mineral called calcium carbonate, which gradually builds up, creating unique shapes.

One well-known cave formation is the stalactite. These icicle-like structures hang from the ceiling and form as water containing calcium carbonate seeps through the rock above. The water drips downward, leaving behind minerals that build up over time.

Directly below that, stalagmites form on the cave floor as calcium carbonate drips from the ceiling. These formations grow upward as mineral-rich water drips down, leaving behind deposits.

If a stalactite and stalagmite grow long enough to meet, they form a column, creating a solid mineral pillar inside the cave.

Another example of mineral deposits is found in the Naica Mine in Mexico, where giant shimmering gypsum crystals formed in hot, mineral-rich groundwater over thousands of years.