Stalactite

Elongated mineral formation hanging down from a cave ceiling

A stalactite (UK: , US: ; from Ancient Greek σταλακτός (stalaktós) 'dripping', from σταλάσσειν (stalássein) 'to drip') is a mineral formation that hangs from the ceiling of caves, hot springs, or man-made structures such as bridges and mines. Any material that is soluble and that can be deposited as a colloid, or is in suspension, or is capable of being melted, may form a stalactite. Stalactites may be composed of lava, minerals, mud, peat, pitch, sand, sinter, and amberat (crystallized urine of pack rats).

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