That's partially correct! Stalactites do grow downwards from the ceiling of a cavern, not upwards from the bottom.

Here's a breakdown:

* Stalactites: These are the icicle-shaped formations that hang from the ceiling of a cave. They form when water containing dissolved minerals, like calcium carbonate, drips from the ceiling. As the water evaporates, the minerals are deposited in a ring around the drip point, slowly building a cone-shaped structure.

* Stalagmites: These are the upward-growing formations that rise from the floor of a cave. They form when the water drips from the stalactite and hits the floor, leaving behind mineral deposits. Over time, these deposits accumulate, building a column-like structure.

So, while stalactites do involve mineral deposits, they grow downwards from the ceiling, not upwards from the bottom.