Introduction to magazine feature Kids Page and accompanying "Learn a New Word" segment.

Stalactites & Stalagmites

Make Your Own

When water containing calcium carbonate and other minerals drips from the roof of an underground cave, stalactites and stalagmites are formed. Each drip from ceiling to floor leaves behind some minerals on the roof and drops some more on the floor beneath. Very slowly, the minerals accumulate, creating icicle-like rocks on the ceiling (stalactites) with pointed rocks sticking up from the ground (stalagmites). Once a stalactite and stalagmite grow together, they are called a column.

Stalactites and stalagmites take many thousands to millions of years to form and can be quite beautiful, because different minerals change the color of the rock. To see some examples, you can look at the Stone Showcase on page 19. Onyx comes from stalactites and stalagmites and the different dripping minerals form the patterns that can be seen in many of the Stone Showcase images.

We don’t know about you, but we’ve always thought stalactites and stalagmites were pretty cool. We also wish someone had told us we could make some of our own when we were in grade school! But it’s never too late, so former staffer, Brian, grabbed his niece and nephew and tried out the experiment outlined on pages 28-33. And we took pictures!

This experiment doesn’t make the same kinds of stalactites and stalagmites you might find in a cave, but we figured you probably didn’t want to wait thousands of years to see the result, so...

You can think of this as the same process on fast forward.

Learn A New Word (or three)

Stalactite noun

Put simply, a stalactite is a rock formation that hangs from the ceilings of caves, hot springs, and even man-made structures like mines and bridges.

Stalagmite noun

As you already know, stalagmites are the counterparts or buddies of stalactites. They are rock formations that grow up from the floor as minerals accumulate from ceiling drippings.

Great, so now you know, but how do you remember which one is which?

We had a lot of trouble with that until we learned these little tricks:

1. Stalactites hold "tite" to the ceiling (stalactites also has a "c" for ceiling in it!).

2. Stalagmites stand up from the ground with all their "mite" (and there's a "g" for ground in stalagmites).

Both stalactites and stalagmites are "speleothems," our third new word.

Speleothem noun

Here's a fun one. If we tell you that all stalactites and stalagmites are speleothems, but not all speleothems are stalactites or stalagmites can you guess what it is? Yup, you got it. A speleothem is a cave formation or “secondary mineral deposit“ (that means it formed after the cave was already there) that forms in caves.

There are lots of types of speleothems and they sound so cool you might want to look them up—cave bacon, cave popcorn, soda straws, curly fries (we kid you not! there is a kind of speleothem called curly fries. Hungry yet? You might not be after the next one...), "clumps of worms," calcite rafts, and snottites (seriously—snottites! and yes, they're called that because they look like snot. Told you they sounded cool... Ok, that one sounds kinda gross, but... still cool...)