thunder egg
Hollow volcanic stone
A thunder egg is a rounded nodule of rock, typically the size of a baseball, with a plain exterior that conceals an interior of agate, opal, or crystal.
Found in volcanic ash beds, they must be cut open to reveal the colorful formations inside.
The name comes from Native American legends attributing them to thunder spirits.
Banded semiprecious stone
- chalcedonyTranslucent microcrystalline silica variety
- quartzCrystalline silicon dioxide
- crystalOrdered-atom solid
- amethystPurple semiprecious quartz
cavity · nodule · silica · formation · rockhound · mineralogy · banding · concentric
Pale volcanic igneous rock
- lavaErupted liquid stone
- ashCombustion's powdery remains
- tuffSolidified volcanic ash
- weldedJoined metals by melting
pyroclastic · eruption · igneous · obsidian · perlite · silica · Oregon · flow
Amateur geology enthusiast
- specimenIndividual for examination
- lapidaryWorker of precious stones
- polishedSmooth, refined, accomplished
- slabbedCovered with flat stones
bookend · display · cabinet · cutting · tumbling · gem show · souvenir · gift shop
Adding decorative strips
- patternRecurring arrangement or template
- concentricSharing one center
- colorfulFull of varied hues
- polishedSmooth, refined, accomplished
cross-section · rings · swirls · fortification · landscape · scenic · moss · plume
agate
Banded semiprecious stone
- chalcedonyTranslucent microcrystalline silica variety
- quartzCrystalline silicon dioxide
- crystalOrdered-atom solid
amethyst · cavity · nodule · silica · formation · rockhound · mineralogy · banding · concentric · hollow
rhyolite
Pale volcanic igneous rock
welded · pyroclastic · eruption · igneous · obsidian · perlite · silica · Oregon · flow · cooling
rockhound
Amateur geology enthusiast
- specimenIndividual for examination
- lapidaryWorker of precious stones
- polishedSmooth, refined, accomplished
slabbed · bookend · display · cabinet · cutting · tumbling · gem show · souvenir · gift shop · natural history
banding
Adding decorative strips
- patternRecurring arrangement or template
- concentricSharing one center
- colorfulFull of varied hues
polished · cross-section · rings · swirls · fortification · landscape · scenic · moss · plume · dendritic
thunder eggfossil
Preserved ancient organism
petrified wood · sedimentary rock · limestone · coral · ammonite
thunder, egg, thunders, thundered, thundering, thunderous, thunderously, thunderbolt, thunderclap