Synthetic Glass (Often Categorized As A Simulated Mineral)

Chert Nodules (with Gryphaea or Shell inclusions)

Microcrystalline Quartz (SiO2) with Calcitic inclusions

Chert (Flint variety)

Chert (Cryptocrystalline Quartz, SiO2)

Rhodochrosite

Manganese Carbonate (MnCO3)

Chert (varieties include Flint and Jasper)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Schist

N/A (a rock type, not a mineral formula)

Limonite after Pyrite (Prophecy Stone or Ironstone Concretion)

Goethite/Limonite pseudomorph after Pyrite/Marcasite (FeO(OH)·nH2O)

Sunstone

Aventurine Feldspar (Plagioclase Feldspar with inclusions)

Chrysocolla and Azurite in Matrix

Hydrated copper phyllosilicate (Chrysocolla - Cu2H2Si2O5(OH)4) and Copper carbonate (Azurite - Cu3(CO3)2(OH)2)

Chert

Microcrystalline Quartz (SiO2)

Quartzite (River Siltstone variety)

Quartzite (SiO2)

Quartz (Variety of Rough Mineral Specimens)

Silicon Dioxide (SiO2)

Chert (Jasper/Agate variety)

Microcrystalline Quartz (SiO2)

Sandstone

Arenite (general term for sandstone)

Sandstone

Arenite (SiO2 based with various mineral cements)

Quartzite River Rock

Quartzite (primarily SiO2)

Chert (Jasper)

Silicon Dioxide (SiO2) with impurities

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Chert (Jasper or Flint variant)

Chert (composed of microcrystalline quartz, SiO2)

Chert (Flint) Nodule

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (often called Flint in various colors)

Silicon Dioxide (SiO2)

Quartzite Pebble

Metamorphic Quartzite (primarily SiO2)

Chert (Jasper variation)

Chert (Microcrystalline Silicon Dioxide, SiO2)

Banded Chert (Agate)

Silicon Dioxide (SiO2)

Chert (Banded)

Chert (Microcrystalline Silicon Dioxide, SiO2)

Chert (River Pebble)

Microcrystalline Quartz (SiO2)

Chert (often called Flint when dark)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Agate

Agate (a cryptocrystalline variety of Quartz, SiO₂)

Hematite

Hematite (Fe2O3)

Chert (Jasper)

Silicon dioxide (SiO2)

Dumortierite Quartz

Dumortierite (Al7BO3(SiO4)3O3 / inclusion in SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Quartzite

Metamorphosed Sandstone (SiO2)

Yellow Quartzite Pebble

Quartzite (SiO2)

Druzy Chalcedony/Quartz on Fluorite core

Silicon Dioxide (SiO2) on Calcium Fluoride (CaF2)

Rose Quartz

Quartz (Silicon Dioxide) - SiO2

Pyrite (on host rock)

Iron Sulfide (FeS2)

Chert (specifically Red Chert or Jasper)

Microcrystalline Quartz (SiO2)

Pyrite

Iron Sulfide (FeS2)

Bloodstone / Heliotrope

Silicon dioxide (SiO2) with inclusions

Agate (various color varieties)

SiO₂ (Silicon Dioxide)