Sedimentary Rock (Possibly Composed Of Various Minerals)

Shiva Lingam

Cryptocrystalline Quartz (Jasproid/Jasper)

Sandstone (with Lichen)

Arenite (primarily SiO2)

Limonite or Ironstone Nodule

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

Limonite Nodule

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

Limonite

FeO(OH)·nH2O

Sandstone

Arenite (SiO2 based)

Sandstone

Arenite (SiO2 based)

Sandstone (Quartzose)

Sandstone (composed primarily of Quartz: SiO2)

Pyrite (Fool's Gold) in Matrix

Iron Disulfide (FeS2)

Quartz Crystal Cluster

Silicon Dioxide (SiO2)

Sandstone

Quartzose Sandstone (Sedimentary Rock)

Granite

Phaneritic Felsic Igneous Rock (composed primarily of Quartz, Feldspar, and Mica)

Granite

Phaneritic Felsic Igneous Rock (composed primarily of Quartz and Alkali Feldspar)

Chert (Jasper variation)

Silicon Dioxide (SiO2)

Sandstone

Sedimentary Rock (Quartz arenite/Arkosic sandstone)

Chert (Arrowheads)

Microcrystalline Quartz (SiO2)

Quartz with inclusions

SiO2

Sandstone

Clastic Sedimentary Rock

Sandstone Pebble

Arenite (typically SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Sedimentary Outcrop (Sandstone/Shale)

Sedimentary bedrock formation (variable composition)

Quartzite

Quartzite (primarily composed of SiO O₂)

Granite (likely biotite granite or granodiorite)

Coarse-grained granitoid composed mainly of quartz, feldspar, and dark biotite/hornblende

Pegmatite (Granitic Pegmatite)

Pegmatite (Quartz + Potassium Feldspar + Mica)

Diorite

Intermediate Intrusive Igneous Rock

Pebbles

Polymictic rock fragments

Quartz Pebble

Silicon Dioxide (SiO2)

Coal

Carbonaceous sedimentary rock

Jasper

Microcrystalline Quartz (SiO2)

Sandstone

Sedimentary Rock (Quartz Arenite)

Polished agate or jasper cabochon

Cryptocrystalline quartz, SiO₂, possibly iron-rich jasper inclusions

Sandstone

Arenite (SiO2 primarily)

Weathered mafic rock, likely basalt or greenstone

Fine-grained basaltic rock; possibly altered basalt (metabasalt/greenstone)

Polished jasper pebble

Jasper, microcrystalline quartz (SiO₂) with iron-oxide and clay-mineral impurities

Sandstone

Sandstone (composed mainly of Quartz, SiO2, and Feldspar)

Lapis Lazuli (Tumbled)

Lazurite-dominated contact metamorphic rock

Lapis Lazuli

Na8[Al6Si6O24]Sn (Lazurite-rich metamorphic rock)

Quartz (likely macrocrystalline variety)

Quartz (SiO₂)

Quartz Crystal

Silicon Dioxide (SiO2)

Chalcedony (Agate)

Silicon Dioxide (SiO2)

Mica-bearing quartz rock (likely pegmatite)

Quartz–feldspar–mica pegmatite; dark mica is probably biotite, possibly muscovite or chlorite

Crinoid Fossil in Limestone

Crinoid columnal (Class Crinoidea) in biomicrite