Sedimentary (Chemically Precipitated) Or Metamorphic

Quartz

Silicon Dioxide (SiO2)

Ferruginous Quartz on Ironstone

Silicon Dioxide (SiO2) with Hematite (Fe2O3)

Quartz Druzy / Quartz Crystal Cluster

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Quartz (Milky / Massive Quartz)

Silicon Dioxide (SiO2)

Pyrite

Iron Sulfide (FeS2)

Orange Calcite

Calcite (Calcium Carbonate, CaCO3)

Quartz (Raw Chunk)

Silicon Dioxide (SiO2)

Quartz (Milky/Clear variety)

Silicon Dioxide (SiO2)

Orange Calcite

Calcium Carbonate (CaCO3)

Limonite/Goethite Concretion

Goethite (FeO(OH))

Green Calcite

Calcium Carbonate (CaCO3)

Clear Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Quartz (Peach/Orange)

Silicon Dioxide (SiO2)

Pyrite

Iron Sulfide (FeS2)

Optical Calcite

CaCO3 (Calcium Carbonate)

Quartz

Silicon Dioxide (SiO2)

Quartz Geode Cluster (Iron-stained Quartz)

Silicon Dioxide (SiO2)

Pyrite

Iron Sulfide (FeS2)

Calcite

Calcium Carbonate (CaCO3)

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Pyrite-bearing Rock / Pyrite Ore

Iron Sulfide (FeS2) in host rock matrix

Calcite

Calcium Carbonate (CaCO3)

Gneiss with Quartz Veining

Gneiss (High-grade Metamorphic Rock)

Honey Calcite

Calcium Carbonate (CaCO3)

Quartz (Milky/Clear)

Silicon Dioxide (SiO2)

Hematite

Iron(III) oxide (Fe2O3)

Gold Ore

Native Gold (Au)

Specular Hematite (Specularite)

Hematite (Alpha-Fe2O3)

Jasper

Microcrystalline Quartz (SiO2)

Banded Onyx (Green Onyx)

Banded Calcite or Travertine (CaCO3)

Orange Calcite

Calcium Carbonate (CaCO3)

Quartz / Quartzite

Silicon Dioxide (SiO2)

Blue Calcite

Calcium Carbonate (CaCO3)

Orange Calcite

Calcium Carbonate (CaCO3)

Green Calcite

Calcite (Calcium Carbonate, CaCO3)

Chert or Flint

Silicon dioxide (SiO2)

Chert

Microcrystalline Quartz (SiO2)