Man Made Composite (Lithified Equivalent Of Sedimentary)

Calcite-rich limestone (possibly fossiliferous limestone)

Calcite, CaCO₃, in a limestone matrix

Puddingstone

Polymictic Conglomerate

Goldstone

N/A (Synthetic Glass with Copper Inclusions)

Calcite-rich limestone (possibly crystalline limestone)

Calcite, CaCO₃, in limestone; locally recrystallized toward marble

Perforated beach pebble (likely sandstone or chert)

Indeterminate siliciclastic sedimentary rock; predominantly quartz (SiO₂), possibly calcareous cement

Polished brown chalcedony (likely carnelian or jasper)

Microcrystalline quartz, SiO₂; iron oxides produce the brown coloration

Fossiliferous Limestone

Limestone with embedded fossil cross-section

Breccia

Clastic Breccia (SiO2/CaCO3 dominated)

Rounded limestone pebble

Micritic limestone, composed mainly of calcite (CaCO₃)

Chert (Cherty Shale / Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Weathered iron-rich sandstone or ironstone pebble

Ferruginous sandstone; predominantly quartz (SiO₂) cemented or stained by iron oxides/hydroxides

Sandstone

Arenite (clastic sedimentary rock)

Chert (Flint)

Silicon dioxide (SiO2)

Rounded sandstone pebble

Quartz-rich sandstone, likely ferruginous or arkosic sandstone

Sandstone

Sedimentary Rock (Quartz arenite)

Tumbled aqua glassy mineral specimen, likely chrysocolla or turquoise imitation

Uncertain from image; possible chrysocolla (hydrated copper aluminosilicate, variable composition) or dyed/man-made glass

Weathered sandstone or quartz-rich sedimentary cobble

Indeterminate sandstone, likely arkose or quartz arenite

Likely limestone or chalk

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

Weathered fossil-bearing limestone, possibly coral or shell limestone

Calcite-rich limestone (CaCO₃); fossil identity is uncertain from the photograph

Rounded quartz-rich pebble

Likely quartzite or quartz-rich sandstone; predominantly SiO₂

Weathered sandstone or iron-stained quartzite

Quartz-rich sandstone; possibly weakly metamorphosed quartzite (SiO₂-dominant)

Tumbled brown pebble

Indeterminate; likely quartz-rich sandstone or chert

Weathered limestone or calcareous fossil fragment

Calcite-rich carbonate rock (CaCO₃), possibly fossiliferous limestone

Crinoid and Coral Fossils in Limestone

Fossiliferous Limestone with Rugosa (order) and Crinoidea (class)

Puddingstone (Gowganda Tillite/Jasper Conglomerate)

Jasper Conglomerate (SiO2 primary composition)

River Rock (Mossy)

Stream-rounded Clast (likely Siltstone or Sandstone with bryophytes)

Conglomerate

Conglomerate (clastic sedimentary rock)

Conglomerate

Conglomerate (clastic sedimentary rock)

Conglomerate

Conglomerate (clastic sedimentary rock)

Weathered conglomeratic sandstone

Polymictic conglomerate or pebbly sandstone, likely iron-stained

Weathered fossiliferous limestone

Calcitic limestone, predominantly calcium carbonate (CaCO₃), possibly bioclastic limestone

Sandstone

Clastic Sedimentary Rock

Fossiliferous limestone

Bioclastic limestone, primarily calcite (CaCO₃)

Reddish-brown sandstone pebble

Quartz-rich sandstone, likely ferruginous sandstone

Flint

SiO2 (Cryptocrystalline Quartz)

Conglomerate

Conglomeratic Sandstone

Small metallic-looking mineral/rock fragment

Indeterminate from image; possibly galena, hematite, or metallic slag

Iron-rich sandstone or ironstone fragments

Ferruginous sandstone; chiefly quartz (SiO₂) cemented or stained by iron oxides such as hematite (Fe₂O₃) and goethite (FeO(OH))

Sandstone

Arenite

Polished fossiliferous limestone, possibly coral or shell fossil

Calcite-rich limestone (CaCO₃), with probable fossilized skeletal structures

Worn quartz-rich pebble

Likely microcrystalline quartz (SiO₂), possibly a weathered chert or milky quartz fragment

Fossilized gastropod (likely nerite or related sea snail)

Gastropoda; shell composed originally of aragonite/calcite, commonly replaced or infilled by calcite