Sedimentary (Fossil)

Chert (Beach Pebble)

Microcrystalline Quartz (SiO2)

Banded Iron Formation

Banded Iron Formation (BIF)

Glauconitic Sandstone

Glauconitic sandstone ((K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)

Chert with Limestone

Microcrystalline Quartz (SiO2) in Calcium Carbonate (CaCO3) matrix

Chert / Quartz Pebble

Silicon Dioxide (SiO2)

Coquina / Fossiliferous Limestone

Fossiliferous Limestone / CaCO3

Jasper with Hematite Inclusions

Silicon Dioxide (SiO2) with Ferric Oxide (Fe2O3)

Limonite (Ironstone Concretion)

Hydrated iron(III) oxide-hydroxide (FeO(OH)·nH2O)

Chert (Chalcedony-rich sedimentary rock)

Cryptocrystalline Quartz (SiO2)

Conglomerate

Conglomerate rock

Sandstone with Iron Oxide Coating

Arenite (SiO2 with Fe2O3 impurities)

Jasper

Microcrystalline Quartz (SiO2)

Sandstone (Common Quartz Pebble/Rock)

Sedimentary rock / Quartz arenite

Blue calcite (probable)

Calcite, calcium carbonate (CaCO₃)

Rough amber-like brown mineral specimen

Uncertain from photograph; possibly iron-stained quartz, common opal, or resinous amber

Yellow Jasper

Silicon Dioxide (SiO2) with iron hydroxides

Blue Calcite

Calcium Carbonate (CaCO3)

Red Jasper

Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions

Jasper

Silicon dioxide (SiO2)

Yellow Calcite

Calcium Carbonate (CaCO3)

Yellow Jasper

Silicon dioxide (SiO2)

Geode (Unopened)

Silica-rich concretion (SiO2)

Jasper and Ironstone (likely Jasperized Ironstone)

Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3)

Ocean Jasper

Orbicular Jasper (Silicon Dioxide, SiO2)

Selenite / Gypsum

Gypsum (CaSO4·2H2O)

Chert Nodules in Sedimentary Rock

Microcrystalline Quartz (SiO2) within Clastic Matrix

Sandstone

Sandstone (SiO2 predominant)

Red Sandstone

Sandstone (principally Quartz, SiO2, with Iron Oxide hematite cement)

Rounded sedimentary pebble, likely mudstone or shale

Argillite/mudstone; predominantly compacted clay minerals with quartz and iron oxides

Sandstone (Heart-shaped pebble)

Sedimentary Quartz Sandstone

Sandstone

Clastic Sedimentary Rock

Sandstone (Weathered Fragment)

Clastic Sedimentary Rock

Quartz-veined Sedimentary Rock

Sedimentary rock with hydrothermal quartz veins

Quartz Vein in Basalt or Sedimentary Host Rock

Silica-veined lithic fragment (SiO2 in host matrix)

Vein-filled Sedimentary Rock

Silicified sedimentary rock with quartz/calcite vein

Quartz and Mixed Sedimentary Rocks

Silicon Dioxide (SiO2) mixed with various clastic sedimentary lithologies

Sandstone

Sedimentary Rock (Quartz Sandstone)

Sandstone and River Pebbles

Sedimentary Rock (Sandstone / Quartzite / Chert)

Chert (Yellow Jasper variant)

Microcrystalline Quartz (SiO2)

Red Sandstone

Arenite (Ferruginous Sandstone)

Puddingstone (Gowganda Tillite/Lorrain Quartzite)

Jasper Conglomerate

Limestone (or Sandstone)

Calcium Carbonate (CaCO3) / Silica (SiO2)