Sedimentary (Fossiliferous)

Fossiliferous Sandstone with Plant Remains

Arenite with Carbonaceous impressions (likely Paleozoic/Mesozoic Flora)

Weathered fossiliferous limestone, possibly coral or stromatoporoid

Calcitic limestone, predominantly CaCO₃; fossil identity cannot be confirmed from one photograph

Fossiliferous limestone, likely crinoidal limestone

Bioclastic limestone; predominantly calcite (CaCO₃), with possible dolomite and silicate impurities

Rounded fossiliferous limestone or weathered limestone nodule

Likely bioclastic limestone, composed mainly of calcite (CaCO₃); exact identification is limited by the blurry image

Chert (potentially Fossiliferous or Jasperoid)

Microcrystalline Quartz (SiO2)

Weathered fossiliferous sandstone or mudstone cobble

Lithified siliciclastic sediment; the raised curved feature may be a trace fossil or shell impression

Limestone

Calcium Carbonate (CaCO3)

Weathered limestone

Calcite-rich limestone (CaCO₃), possibly fossiliferous or bioclastic

Pale limestone or calcite-rich rock

Calcite (CaCO₃), likely micritic limestone

Rounded limestone pebble

Calcite-rich micritic limestone (CaCO₃), possibly a fossiliferous limestone

Weathered limestone fragment

Limestone, predominantly calcite (CaCO₃), possibly porous bioclastic limestone

Rounded pale pebble, likely limestone

Micritic limestone, primarily calcite (CaCO₃)

Chert or siliceous limestone fragments

Microcrystalline quartz (chert) and/or calcarenite; exact identification is uncertain from the photograph

Fossil-rich limestone

Bioclastic limestone, likely containing bivalve or brachiopod fossils; calcium carbonate (CaCO₃), chiefly calcite

Coquina Limestone (Fossiliferous Limestone)

Calcareous bioclastic sedimentary rock (CaCO3)

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

Chert (microcrystalline SiO₂), tentative

Likely weathered sandstone fragment

Sandstone, composed mainly of quartz (SiO₂) and feldspar grains in a clay, silica, or iron-oxide cement

Weathered limestone or calcarenite fragment

Micritic limestone, likely calcite-dominated (CaCO₃)

Weathered chert or silicified limestone

Microcrystalline quartz (SiO₂), possibly replacing carbonate rock

Weathered sandstone or quartz-rich sedimentary cobble

Indeterminate sandstone, likely arkose or quartz arenite

Weathered limestone or calcareous tufa

Calcite-rich carbonate rock; primarily CaCO₃

Rounded limestone pebble

Micritic or bioclastic limestone, primarily calcium carbonate (CaCO₃)

Likely limestone or chalk

Calcite-rich carbonate rock; predominantly calcium carbonate (CaCO₃)

Light-colored limestone pebble

Calcite-rich limestone (primarily CaCO₃)

Tumbled chert or flint

Microcrystalline quartz (SiO₂), commonly termed chert; dark varieties are called flint

Weathered limestone or calcareous concretion

Calcite-rich limestone; predominantly calcium carbonate (CaCO₃)

Rounded sandstone pebble

Sandstone, predominantly quartz with feldspar and iron-oxide cement

Tan chert or silicified limestone fragment

Microcrystalline quartz (SiO₂), possibly calcareous chert

Tumbled limestone or calcitic rock

Limestone, predominantly calcite (CaCO₃)

Banded limestone or marble

Likely calcite-rich limestone (CaCO₃), possibly weakly metamorphosed marble

Weathered chert or silicified limestone

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

Quartz-rich sandstone (likely arkosic sandstone)

Sandstone, composed mainly of quartz (SiO₂) with feldspar and minor iron-oxide cement

Chalk

Calcium Carbonate (CaCO3)

Chalky limestone

Micritic limestone, predominantly calcite (CaCO₃)

Weathered limestone fragment

Limestone, predominantly calcite (CaCO₃)

Tumbled limestone or calcite-rich stone

Limestone, predominantly calcite (CaCO₃); exact identification is uncertain from the photograph

Weathered chert or flint

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

Weathered sandstone

Quartz-rich clastic sandstone, likely iron-oxide-stained

Banded chert or siliceous mudstone

Microcrystalline quartz (chalcedony), SiO₂; possibly ferruginous shale

Sandstone

Arenite (primarily SiO2 with trace Fe2O3)

Grey Limestone Pebble

Limestone (Calcium Carbonate - CaCO3)

Limestone

Sedimentary rock composed primarily of Calcium Carbonate (CaCO3)