Spathites are a variant of soda straws that are formed from aragonite, rather than calcite, and differences in the crystal structure of these two minerals creates a different morphology. Instead of a simple tube like a soda straw, the spathite is comprised of a series of fan shaped cones that occur singly or multiply, with the top of each new cone growing from the base of the one above, producing a stairstep-like effect. In soda staws the crystals of calcite are parallel to the vertical walls of the tube, whereas in spathites the crystals are at a 60-degree angle to the tube. The cones of the growing spathite enlarge in width until they exceed the width of a water drop and then the drops flow to one side, creating a new cone.
Spathites are rare in general but can be abundant in the caves where they occur. Some of the images on this page are from a large cave in Missouri, while the longer ones are from the tropics, where formations in general tend to grow larger.
These are among the wold's longest spathites, in the Philippines.
The one on the right is about 260 cm in length.
Created: May 25, 2016
Updated: March 8, 2020
Author: Dave Bunnell