Man Made Material (Metal)

Quartzite Pebble

Metamorphosed Quartz Sandstone (SiO2)

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Jasper (Cream/Yellow variety)

Jasper (Microcrystalline Quartz, SiO2)

Polygenetic Conglomerate (Puddingstone)

Conglomerate (SiO2 matrix with mixed clasts)

Quartz (Milky and Smoky variety)

Silicon Dioxide (SiO2)

Sandstone

Arenite (SiO2 predominantly)

Quartz Geode

Silicon Dioxide (SiO2)

Sandstone (likely Arkosic or Quartzose)

Sandstone (SiO2 dominated)

Sandstone (likely Quartzose Sandstone)

Arenite (primarily SiO2)

Marble

Recrystallized Calcite (CaCO3)

Limestone

Calcium carbonate (CaCO3)

Green Common Opal

Hydrated Silica (SiO2·nH2O)

Septarian Nodule (Galt)

Calcareous concretion / Septarian concretion

Sandstone

Arenite (primarily SiO2)

Sandstone

Arenite (SiO2 based)

Sandstone (Ferruginous)

Arenite (primarily SiO2 with Fe2O3 staining)

Greenschist

Greenschist (Chlorite Schist)

Milky Quartz

Silicon Dioxide (SiO2)

Sandstone

Arenite (primarily SiO2)

Sandstone

Arenite (SiO2 based with quartz grains)

Sandstone (Water-worn Cobble)

Arenite (variable composition, primarily SiO2)

Quartzite

Quartzite (primarily SiO2)

Sandstone

Arenite (SiO2 primarily)

Sandstone (with potential iron-oxide staining)

Arenite (primarily SiO2)

Snowflake Obsidian

Spherulitic Volcanic Glass (primarily SiO2)

Sandstone (Ferruginous)

Clastic sedimentary rock (primarily SiO2 with Fe2O3 staining)

Sandstone (Quartzose)

Arenite (SiO2 based)

Sandstone

Clastic Sedimentary Rock (composed of SiO2 grains)

Lepidolite on Pegmatite

Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2) in Granitic Pegmatite

Sandstone

Arenite (primarily SiO2)

Sandstone (Quartzose Sandstone)

Arenite (primarily SiO2)

Porphyritic Basalt (Chinese Writing Stone or Flower Stone)

Porphyritic Basalt / Porphyry

Shale

Laminated Mudstone

Quartz Pebble (with probable inclusions or staining)

Quartz (Silicon Dioxide - SiO2)

Sandstone

Arenite (composed primarily of SiO2)

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with inclusions of Iron Oxide)

Quartz / Common Agate

Silicon Dioxide (SiO2)

Snowflake Obsidian

Obsidian (volcanic glass) with Cristobalite inclusions

Conglomerate

Clastic Sedimentary (Conglomerate)

Thunderegg (specifically a Jasper/Agate-filled Geode nodule)

Silicon Dioxide (SiO2) within Rhyolitic Matrix

Fossiliferous Limestone

Fossiliferous Calclutite / Bio-calcarenite (CaCO3)

Sandstone with Liesegang Rings

Arenite with Iron Oxide Concretions