Organic Gemstone (Not A Rock Or Mineral In The Traditional Sense, But Bio Mineralized Material)

Sandstone

Arenite (primarily SiO2)

Sandstone (likely Quartzose Sandstone)

Clastic Sedimentary Rock (primarily SiO2)

Schist

Mica Schist

Copper-bearing Quartz (with Malachite and Iron Oxides)

Quartz (SiO2) with Malachite (Cu2CO3(OH)2) and Hematite/Limonite (Fe2O3)

Sandstone (with Lichen)

Arenite (composed primarily of SiO2)

Sandstone

Arenite (composed primarily of SiO2)

Fossiliferous Shale

Laminated Mudrock with plant fossils

Sandstone (with Iron Staining)

Clastic sedimentary rock (primarily Quartz with Limonite/Goethite staining)

Sandstone (Red Sandstone / River Stone)

Arenite (composed primarily of Quartz, SiO2, with Iron Oxide cementation)

Banded Gneiss (River Cobble)

Gneiss (a high-grade metamorphic rock)

Quartz

Silicon Dioxide (SiO2)

Jade

Jadeite or Nephrite

Dendritic Agate

Chalcedony (SiO2) with manganese/iron oxide inclusions

Pink Opal (Common Opal)

Amorphous Hydrated Silica (SiO2·nH2O)

Sandstone (Quartzose Sandstone)

Clastic sedimentary rock (SiO2 major component)

Coarse-grained Granite

Phaneritic Granite (contains Quartz, Feldspar, and Mica)

Red Sandstone

Arenite (primarily Quartz with Iron Oxide)

Agate Geode Slice (with Druzy Quartz)

Silicon Dioxide (SiO2)

Moss Agate

Silicon Dioxide (SiO2) with inclusions of manganese or iron oxide

Amber

Fossilized Tree Resin (Succinate)

Sandstone (with Iron Staining)

Clastic sedimentary rock (primarily Quartz with Fe2O3 staining)

Unakite

Epidotized Granite

Chert (Chert Pebble)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Diamond

Diamond (pure Carbon, C)

Amygdaloidal Basalt with Epidote

Vesicular Basalt with secondary Epidote/Quartz mineral infill

Asphalt (Bituminous Pavement)

Bituminous mix (Aggregates with Bitumen binder)

Pearl

Calcium Carbonate (mostly Aragonite), CaCO3 (with conchiolin)

Banded Gneiss

Gneiss (High-grade metamorphic rock)

Amber

Succinite (C10H16O)

Sandstone

Arenite

Sandstone (Pebble)

Arenite (primarily SiO2)

Sandstone (Red/Brown Variety)

Arenite (SiO2 with iron oxide impurities)

Turquoise in Matrix

Hydrated phosphate of copper and aluminium: CuAl6(PO4)4(OH)8·4H2O

Amber with inclusion

Amber (Fossilized Tree Resin)

Sandstone (Weathered Coastal Boulder)

Arenite (composed primarily of SiO2)

Amber

Organic gemstone (Succinite is common if from the Baltic)

Sandstone

Arenite (SiO2 based)

Sandstone with Ironstone Concretion

Arenite with Hematite/Goethite nodules (Fe2O3 / FeO(OH))

Sandstone (Red)

Arenite (SiO2 with Fe2O3)

Petrified Wood

Silicified Wood (SiO2)

Red Jasper

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Red Sandstone

Arenite (primarily Quartz with Hematite cement)