Sedimentary (Secondary Mineral Formation)

Lepidolite with Rubellite Tourmaline

K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2 (Lepidolite mica)

Chalcedony (Yellow Agate/Chert)

Silicon Dioxide (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hematite (Iron Ore)

Hematite (alpha-Fe2O3)

Sandstone (Ferruginous)

Arenite with Iron Oxide cement

Garnet Schist or Garnet-bearing Quartzite

Metamorphic rock containing Almandine Garnet (Fe3Al2(SiO4)3) and Quartz (SiO2)

Sandstone

Arenite (SiO2 + various cementing minerals)

Sandstone (Ferruginous)

Arenite (composed primarily of SiO2 with Fe2O3 cement)

Bornite (Peacock Ore)

Bornite (Cu5FeS4)

Sandstone

Sandstone (Sedimentary rock composed of silicate grains)

Red Jasper

Jasper (Silica with Iron Oxide inclusions), SiO2

Sandstone

Arenite (primarily SiO2)

Limestone

Sedimentary rock composed of Calcium Carbonate (CaCO3)

Jasper

Jasper (Silicon Dioxide, SiO2)

Carnelian (Chalcedony)

Silicon Dioxide (SiO2)

Yellow Jasper

Silicon Dioxide (SiO2) with iron impurities

Sandstone

Arenite (SiO2 principal)

Sandstone (Quartzose)

Arenite (primarily SiO2)

Sandstone

Arenite (composed primarily of SiO2)

Sandstone or Mudstone with Iron Staining

Ferruginous Sandstone/Mudstone

Fancy Jasper

Chalcedony (cryptocrystalline quartz) with inclusions

Sandstone (Quartz Arenite)

Clastic Sedimentary Rock - Quartz Arenite

Almandine Garnet in Schist

Almandine Garnet (Fe3Al2(SiO4)3) in Mica Schist

Hematite (Oolitic or Earthy variety)

Iron(III) oxide (Fe2O3)

Hematite

Iron(III) oxide (Fe2O3)

Hematite Nodule

Hematite (Fe2O3)

Limestone

Sedimentary Calcium Carbonate (CaCO3)

Red Sandstone

Arenite (with Iron Oxide / Hematite cementation)

Amethyst

Amethyst (Silicon Dioxide, SiO2)

Quartz (likely tumbled or naturally water-worn)

Quartz (SiO₂ - Silicon Dioxide)

Basalt with Amygdules

Amygdaloidal Basalt

Sandstone (with banding)

Arenite (primarily SiO2)

Black Tourmaline

Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)

Red Jasper

Silicon Dioxide with Hematite inclusions (SiO2 + Fe2O3)

Druzy Quartz (on Geode Fragment)

Silicon Dioxide (SiO2)

Almandine Garnet

Almandine (Fe3Al2(SiO4)3)

Hematite

Iron(III) oxide (Fe2O3)

Banded Agate (specifically Carnelian Agate slice)

Chalcedony (cryptocrystalline variety of Quartz), SiO2

Hematite

Iron(III) oxide (Fe2O3)

Sandstone

Arenite (Sedimentary rock composed of sand-sized minerals or rock grains)

Kambaba Jasper (Crocodile Jasper)

Stromatolitic Rhyolite/Jasper (SiO2)

Marble

Recrystallized Carbonate Rock (CaCO3)