At various places in the world, certain rocks make an inexplicable ringing sound when hit with a hammer or mallet. Geologists who have studied these ringing rocks can come up with no explanation for the phenomenon, though others have suggested that the ringing might be due to fields of Earth energy at such sites. However, when the rocks are removed from their natural site, they still ring. In fact, they even ring after being broken. One area with an unusually large number of ringing rocks is southeastern Pennsylvania, and most of the research on the phenomenon has been conducted there.
- Earth Energy
The Greenhaven Encyclopedia of Paranormal Phenomena – written by Patricia D. Netzley © 2006 Gale, a part of Cengage Learning