Cave Popcorn
Detailed Description
A series of bulbous cave formations known as "cave popcorn." The geode-like formation in the center developed, because, at one point, this portion was submerged in water. Water was moving on the surface, creating the smooth appearance, while the opening allowed water to pool. The still water deposited dissolved calcium carbonate in the form of calcite crystals to create the distinctive formation.
Sources/Usage
Public Domain.