Sedimentary Rock (Specifically A Chemical Sedimentary Rock, Or A Chert If Considered Purely Mineral Aggregate)

Gneiss

Gneiss (High-grade regional metamorphic rock)

Sandstone (Pebble)

Arenite (primarily SiO2)

Pickled Dragon Eggs (Fictional Interpretation: Purple Agate or Amethyst Geodes)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

White Precious Opal

Hydrated Silica (SiO2·nH2O)

Quartz Geode

Silicon Dioxide (SiO2)

Pink Opal (Common Opal)

Amorphous Hydrated Silica (SiO2·nH2O)

Yellow Jasper

Silicon Dioxide (SiO2) with Goethite/Limonite inclusions

Carnelian

Carnelian (Silicon Dioxide - SiO2)

Sandstone (Greywacke/Lithic Sandstone)

Arenite / Lithic Sandstone

Quartz

Quartz (SiO2, Silicon Dioxide)

Quartz (on matrix)

Quartz (Silicon Dioxide, SiO₂)

Sandstone (Wonderstone)

Silicified Sandstone / Orthoquartzite with Liesegang rings

Carnelian (Orange Agate)

Silicon Dioxide (SiO2)

Blue Agate (Dyed)

Silicon Dioxide (SiO2)

Quartz (Milky or Common Quartz)

Silicon Dioxide (SiO2)

Clear Quartz Crystal

Silicon Dioxide (SiO2)

Chalcedony (Agate/Carnelian precursor)

Chalcedony (Silicon Dioxide, SiO2)

Sandstone (Ferruginous)

Arenite (primarily SiO2 with iron oxide staining/cementing)

Sandstone with Vitrinite/Coal inclusions

Arenite with Carbonaceous inclusions

Sandstone (Quartzose)

Arenite (Formula: SiO2 primary, with various cements)

Red Sandstone

Sandstone (mainly SiO2 with Iron Oxide cement)

Sandstone (Ferruginous)

Clastic Sedimentary Rock (primarily SiO2 with Fe2O3 staining)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Red Quartz (Carnelian/Red Jasper Agate)

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Mica Schist

Mica Schist (primarily Muscovite and Quartz)

Gneiss (Banded Gneiss)

Gneiss

Banded Gneiss

Gneiss (High-grade regional metamorphic rock)

Quartz Druze on Matrix (Geode Fragment)

Quartz (Silicon Dioxide, SiO2)

Red Sandstone

Arenite (with Iron Oxide cement)

Gneiss

Gneiss (High-grade Metamorphic Rock)

Sandstone (Red Arkose)

Sandstone (Arkose variant, primarily SiO2 with KAlSi3O8)

Sandstone (Red Sandstone)

Clastic Sedimentary Rock (primarily SiO2 with Iron Oxide)

Petrified Wood

Silicified Wood (primarily SiO2 - Silicon Dioxide)

Gneiss (Schistose)

Gneiss

Sandstone

Arenite (SiO2 based clastic rock)

Yellow Quartz (Citrine Quartz variety / Ferruginous Quartz)

Silicon Dioxide (SiO2) with iron inclusions

Biotite Schist (likely)

Biotite Schist (rock), Biotite (mineral)

Chalcedony (Quartz Nodule)

Silicon Dioxide (SiO2)

Limonite (Iron Ore)

FeO(OH)·nH2O (Hydrated Iron Oxide)

Quartzite Beach Pebble

Quartzite (primarily SiO2)

Mica Schist

Mica Schist (Composition typically contains Muscovite: KAl2(AlSi3O10)(OH)2 or Biotite: K(Mg,Fe)3AlSi3O10(OH)2 along with Quartz and Feldspar)

Clear Quartz (Rock Crystal)

Quartz (Silicon Dioxide, SiO2)