Flowstone
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Flowstones are composed of sheetlike deposits of calcite formed where water flows down the walls or along the floors of a cave. They are typically found in "solution", or limestone caves, where they are the most common speleothem. However, they may form in any type of cave where water enters that has picked up dissolved minerals.
Flowing films of water that move along floors or down positive-sloping walls build up layers of calcium carbonate (calcite), aragonite, gypsum, or other cave minerals. These minerals are dissolved in the water and are deposited when the water loses its dissolved carbon dioxide, meaning it can no longer hold the minerals in solution. The flowstone forms when thin layers of these deposits build on each other, sometimes becoming rounder as the deposit gets thicker.
The deposits may grade into thin sheets called "draperies" where they go over overhanging portions of the wall. Some draperies are translucent, and some have brown and beige layers that look much like bacon (often termed "cave bacon").
Though flowstones are among the largest of speleothems, they can still be damaged by a single touch. The oil from human fingers causes the water to avoid the area, which then dries out.