Sedimentary (Silicified Fossiliferous Chalcedony)

Turritella Agate (Elimia Agate)

Silicified Elimia tenera (formerly misidentified as Turritella)

Turritella Agate (Fossiliferous Chert)

Silicified Elimia tenera (Fossiliferous Chalcedony)

Turritella Agate

Silicified Elimia tenera Fossil (SiO2)

Chert or flint with chalcedony/quartz veins

Microcrystalline silica: primarily quartz (SiO₂), including chalcedony; possible fossiliferous limestone or silicified material

Turritella Agate

Elimia tenera silicified fossiliferous chalcedony

Fossiliferous Jasper / Miriam Stone / Elephant Skin Jasper

Biogenic Chalcedony / Silicified Fossiliferous Limestone

Tumbled yellow chalcedony (likely silicified material)

Microcrystalline quartz, SiO₂; possibly iron-stained chalcedony or fossilized/silicified limestone

Fossiliferous limestone with silicified fossil material

Bioclastic limestone; likely marine mollusk/coral fragments, locally replaced by chalcedony or calcite

Weathered chert or siliceous mudstone

Microcrystalline quartz (chalcedony), SiO₂; possibly silicified mudstone

Yellow-brown chert or silicified rock fragment

Microcrystalline quartz (SiO₂), likely chert or chalcedony-rich material

Mookaite Jasper

Silicified Radiolarite (SiO2)

Fossiliferous wood / petrified wood fragment

Silicified or partially mineralized wood (fossil wood; commonly quartz/chalcedony replacement)

Weathered quartz-rich rock, likely chert or silicified limestone

Microcrystalline quartz (chalcedony, SiO₂), possibly with calcite (CaCO₃) and iron oxides

Banded chert or siliceous sedimentary rock

Microcrystalline quartz (chalcedony), SiO₂, with iron-oxide staining and possible carbonate/clay layers

Turritella (Gastropod Fossil)

Turritella (Genus of gastropods), CaCO3 (Calcium Carbonate or Silicified Agate)

Iron-stained fossiliferous rock, possibly fossil wood

Likely silicified/petrified wood in iron-rich silica matrix; exact identification requires microscopy

Coquina Jasper

Fossiliferous Chalcedony (SiO2)

Chert (with Fossiliferous Silicification)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Fossiliferous Sandstone (with Quartz patch)

Sedimentary Sandstone with Silicified Shell Fragments

Chert or silicified sedimentary fragment (tentative)

Microcrystalline quartz (SiO₂), possibly silicified limestone or fossil-bearing chert

Red Jasper with Fossils

Silicified Fossiliferous Jasper (Chert variant, SiO2)

Rounded chert or silicified limestone pebble

Microcrystalline quartz (SiO₂), possibly fossiliferous or iron-stained carbonate host

Oolitic Limestone / Fossiliferous Chert

Oolitic Limestone (CaCO3) / Silicified Limestone

Fossiliferous Limestone (Chertified Limestone)

Calcium Carbonate (CaCO3) often replaced by Microcrystalline Silica (SiO2)

Weathered chert or flint

Microcrystalline quartz (SiO₂), likely chert; exact variety uncertain from photo

Fossilized Brachiopod

Phylum Brachiopoda (likely Order Spiriferida or Orthida)

Chert or silicified fossil nodule (tentative)

Microcrystalline quartz (SiO₂), possibly fossiliferous chert

Chert or silicified limestone (uncertain)

Microcrystalline quartz (SiO₂), possibly calcitic limestone (CaCO₃)

Weathered chert or silicified limestone

Microcrystalline quartz (SiO₂), likely chert formed by silicification of carbonate rock

Weathered chert or silicified limestone nodule

Microcrystalline quartz (SiO₂), possibly replacing limestone; exact identification requires testing

Fossiliferous Sandstone / Quartzite Pebble

Sedimentary rock with skeletal fragments (e.g., Paleozoic crinoid/brachiopod fossils)

Petrified Wood

Silicified Wood (SiO2)

Rounded gray stone, likely weathered chert or quartz-rich river pebble

Chert (microcrystalline SiO₂), tentative

Quartz-rich breccia or silicified breccia

Cryptocrystalline quartz/chalcedony (SiO₂) with iron oxides and dark lithic fragments; exact classification is uncertain from the photograph

Augite Shell / Turret Snail Fossil (or Recent Seashell)

Gastropoda (Class) / Turritellidae (Family)

Fossiliferous limestone / shell hash rock

Bioclastic limestone (calcarenite or coquina), dominantly CaCO₃

Chert or flint fragment

Microcrystalline quartz (SiO₂), likely silicified rock

Mookaite Jasper

Radiolarite (Silica, SiO2)

Weathered chert or silicified limestone

Microcrystalline quartz (SiO₂), possibly replacing carbonate rock

Tan chert or silicified limestone fragment

Microcrystalline quartz (SiO₂), possibly calcareous chert

Petrified Wood

Silicified Wood (SiO2)

Brown chert or silicified limestone fragment

Microcrystalline quartz (SiO₂), possibly occurring as chert; exact identification requires testing