hydrolith
/ˈhaɪdrəlɪθ/
noun
- A stony or mineral deposit formed from water, such as a geode or certain cave formations.
- The museum displayed a large hydrolith that looked like a crystal ball.
- The cave was full of beautiful hydroliths that had formed over thousands of years.
- Geologists collected a hydrolith sample to study how minerals crystallize in water.