Thunder Egg — mineral Identification & Properties | Geo-Gem
Thunder Egg is a mineral. Thunder eggs are spherical nodules formed in volcanic ash layers. Similar to geodes but typically solid or mostly filled with agate, jasper, or opal. Named from Native American legend that thunder spirits threw them during storms.
Explore Geo-Gem
- AI Rock & Mineral Identification — snap a photo and get an instant AI-powered ID
- Community Discoveries — browse finds from rockhounds around the world
- Field Guide — regional guides to rocks, minerals, and geology
- Rock & Mineral Database — comprehensive identification reference
- Marketplace — buy and sell specimens with verified collectors
- Rockhound Groups — join local clubs and online communities
- Events & Field Trips — upcoming geology events near you
- Leaderboard — top contributors in the community