GUIDE
Cave & Stalactite Explorer Guide
Learn together · approximately ages 4–8
Explore how water can shape limestone caves and build delicate mineral formations over very long stretches of time.
Six facts to share
Some caves form in limestone
Slightly acidic groundwater can slowly dissolve limestone along cracks, making openings larger over time.
Water carries dissolved minerals
As water travels through limestone, it can carry dissolved calcite into an air-filled cave.
Stalactites grow downward
When mineral-rich water drips from a cave ceiling, tiny deposits can build a stalactite that hangs down.
Stalagmites grow upward
Drops that land on the cave floor may leave minerals behind and build a rounded stalagmite from the ground up.
Columns can join
If a stalactite and stalagmite keep growing until they meet, they form a column.
Cave formations are delicate
A touch can transfer dirt and oils, so protected formations should be admired without touching.
Explorer word bank
- Limestone
- A sedimentary rock that can be dissolved by slightly acidic water.
- Calcite
- A mineral commonly found in limestone and many cave formations.
- Stalactite
- A mineral formation that hangs from a cave ceiling.
- Stalagmite
- A mineral formation that grows upward from a cave floor.
- Speleothem
- The scientific name for a mineral deposit formed inside a cave.
Model a growing cave formation
Use paper and pencils to make a time-sequence model. Real formations grow too slowly for a quick experiment.
- Draw four cave boxes in a row and add a crack above each ceiling.
- In box one, draw one mineral-rich drop hanging from the ceiling.
- In each next box, make the stalactite longer and the stalagmite taller.
- In the final box, join them as a column and label every formation.
Ask your explorer
- Which formation grows from the ceiling?
- What role does water play in making a limestone cave?
- Why should explorers avoid touching cave formations?
- Can you find Crystal Caverns on Dr. Rexington’s map?
Grown-up safety note
Only enter caves that are open to visitors and stay with a trained guide or responsible grown-up. Wear suitable footwear, stay on paths and never touch, break or collect formations.