Caves, Stalactites and Stalagmites

Speleothems are cave features formed by  minerals. 

The word speleothem comes from the Greek words spelaion meaning "cave" and thema meaning "deposit". 

The most well-known speleothems are stalactites and stalagmites. 

Stalactites grow down from the cave ceiling.

Stalagmites grow up from the cave floor. 

It’s easy to remember which is which: 

Stalactites have a "T" for top and stalagmites have a "G" for ground.

Caves, stalactites and stalagmites are caused by chemical reactions.

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