Speleothems - Gypsum Features

Gypsum Needles near the Muddle Room
Gypsum Needles near the Muddle Room

NPS Photo by Larry Toole

Gypsum crystals are common in some of the dryer parts of the cave. Gypsum, a mineral containing both calcium and sulfur, sometimes takes the form of needle-like crystals that radiate from clusters on the floor of the cave; in other cases, gypsum resembles puffs of cotton, or forms clusters of curved or coiled crystals called gypsum flowers.

Last updated: October 20, 2018

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