ammonite
Coiled shell fossil
An ammonite is an extinct marine mollusk with a spiral shell, related to modern nautiluses and squids.
These fossils are abundant in rocks from the Mesozoic era and are prized by collectors for their distinctive coiled chambers.
The name comes from the Egyptian god Ammon, whose ram horns the shells resemble.
She found an ammonite fossil in the limestone cliff. (Capitalized Ammonite refers to a biblical people.)
Chambered marine mollusk
- tentaclesFlexible grasping appendages
- beakHorny avian mouthpart
- mantleCovering or wrap
- cephalopodTentacled marine mollusk class
mollusk · invertebrate · marine · shell · chambered · buoyancy · predator · squid
Spiraling three-dimensional curve
- coilWound circular arrangement
- whorlSpiral arrangement of ridges
- voluteArchitectural spiral ornament
- curvatureDeviation from flatness
scroll · chambered · logarithmic · Fibonacci · golden ratio · ribbed · ornamented · keel
Age of Reptiles
- JurassicDinosaur-dominated geological period
- TriassicFirst Mesozoic period
- CretaceousFinal Mesozoic period
- DevonianGeologic period, 419-359 million years ago
Permian · Carboniferous · extinction · mass extinction · ancient · dinosaur · ichthyosaur · plesiosaur
Individual for examination
- fossil huntingSeeking preserved ancient organisms
- cabinetEnclosed storage furniture
- displayPresentation for viewing
- curioOdd collectible item
artifact · treasure · polished · iridescent · ammolite · opalescent · rare · museum
Becoming rock-like
- impressionEffect on the mind
- traceMinute remnant or pursue
- remainsContinues in place
- fossilizationOrganic remains becoming mineral
mineralization · cast · matrix · excavation · dig · sedimentation · preservation · specimen
nautilus
Chambered marine mollusk
cephalopod · mollusk · invertebrate · marine · shell · chambered · buoyancy · predator · squid · belemnite
helix
Spiraling three-dimensional curve
curvature · scroll · chambered · logarithmic · Fibonacci · golden ratio · ribbed · ornamented · keel · spire
Mesozoic
Age of Reptiles
- JurassicDinosaur-dominated geological period
- TriassicFirst Mesozoic period
- CretaceousFinal Mesozoic period
Devonian · Permian · Carboniferous · extinction · mass extinction · ancient · dinosaur · ichthyosaur · plesiosaur · belemnite
specimen
Individual for examination
- fossil huntingSeeking preserved ancient organisms
- cabinetEnclosed storage furniture
- displayPresentation for viewing
curio · artifact · treasure · polished · iridescent · ammolite · opalescent · rare · museum · collector
petrification
Becoming rock-like
- impressionEffect on the mind
- traceMinute remnant or pursue
- remainsContinues in place
fossilization · mineralization · cast · matrix · excavation · dig · sedimentation · preservation · specimen · embedded
stratigraphy
Study of rock layers
sandstone · formation · sedimentary · outcrop · layer · bedrock · dating · deposit · chalk · marl
- invertebratesinvertebrate, arthropod, arthropods, mollusk, crustacean
- Mesozoicdinosaurs, Velociraptor, Brachiosaurus, Spinosaurus, pterosaurs
- natural historynatural history, natural history museum, naturalist, naturalists, natural philosophers
- Extinct Animalsdinosaur, dinosaurs, tyrannosaurus, dodo, mammoth
- fossilsdinosaur bones, amber, fossils, fossil, fossil bones
- mollusksclams, mollusk, mollusks, snail, snails
ammonitechambered nautilus
Spiral-shelled ocean mollusk
nautilus · living fossil · squid · octopus · cuttlefish
- ammonium nitrateNitrogen-rich agricultural compound
- ammonia fumes
- ammonia smellAcrid nitrogen compound odor
- ammonia gasAcrid nitrogenous vapor
- ammonia leakEscaped caustic vapor
- ammonia waterDissolved gas in H2O