Synthetic Glass (Often Categorized As A Simulated Mineral)

Fluorite (translucent octahedral crystal)

Calcium fluoride (CaF2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Banded Chert

Microcrystalline Quartz (SiO2)

Black Obsidian

Volcanic Glass (Amorphous Silicon Dioxide, SiO2)

Green Chert

Microcrystalline Quartz (SiO2)

Quartzite Pebble

Quartzite (principally SiO2)

Banded Gneiss (River Rock/Pebble)

Gneiss (specifically a banded variety often found as a river rock)

Quartz (White/Milky Pebble)

Silicon Dioxide (SiO2)

Native Copper (Penny specimen)

Native Copper (Cu)

Sandstone (Banded)

Clastic Sedimentary Rock (primarily SiO2)

Quartzite

Quartzite (primarily SiO2)

Quartzite Pebble

Metamorphosed Quartz Sandstone (SiO2)

River Cobble (likely Quartzite)

Metamorphosed Sandstone (SiO2)

Chert (and Fossilized Brachiopod shell)

Sedimentary Cryptocrystalline Quartz (SiO2)

Chert (Flint)

Chert (Microcrystalline Quartz, SiO2)

Chert (Flint)

Microcrystalline Quartz (SiO2)

Chert (Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Prehnite

Prehnite (Ca2Al(AlSi3O10)(OH)2)

Muscovite Mica

Muscovite - KAl2(AlSi3O10)(OH)2

Quartzite

Quartzite (primarily SiO2)

Quartzite

Quartzite (primarily SiO2)

Chert (Yellow Jasper)

Microcrystalline Quartz (SiO2)

Quartzite

Quartzite (SiO2)

Quartzite

Quartzite (SiO2)

Blue Apatite

Fluorapatite (Ca5(PO4)3F)

Red Quartzite / Jasper-rich Pebble

Quartzite (primarily SiO2 with hematite inclusions)

Quartzite

Metamorphosed Quartz Sandstone

Celestite (Celestine) Geode

Strontium Sulfate (SrSO4)

Pegmatite (with smoky quartz and tourmaline/biotite)

Pegmatitic Granite

Quartzite pebble

Metamorphic rock (mainly SiO2)

Quartzite Pebble

Metamorphic Quartz (SiO2)

Epidote Water-Worn Pebble

Epidote {Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)

Sandstone with Magnetite and Iron Staining

Clastic Sedimentary Rock (contains Fe3O4 and Limonite/Hematite)

Jasper

Silicon dioxide (SiO2)

Quartzite

Quartzite (primarily SiO2)

Quartzite Pebble

Metamorphic Quartz (SiO2)

Chrysocolla on Quartz with Iron Oxides

Cu2-xAlx(H2-xSi2O5)(OH)4·n(H2O)

Chert (Jasper variation)

Silicon Dioxide (SiO2)

Riverstone Quartzite

Quartzite (primarily SiO2)

Green Tourmaline (Verdelite)

Tourmaline Group; often Elbaite (Na(Li,Al)3Al6(BO3)3Si6O18(OH)4) or Dravite (NaMg3Al6(BO3)3Si6O18(OH)4)

Quartz

Silicon Dioxide (SiO2)

Schist

Chlorite/Mica Schist