Sedimentary (Secondary Mineral) Within Igneous

Yellow Chalcedony (Agate)

Silicon Dioxide (SiO2)

Pyrite

Iron Disulfide (FeS2)

Quartz (Milky/Clear Quartz with Iron Inclusions)

Silicon Dioxide (SiO2)

Chert (Banded Variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Prehnite

Prehnite (Ca2Al2Si3O10(OH)2)

Amygdaloidal Rhyolite (often called Lake Superior Agate relative)

Rhyolite with Calcite/Quartz amygdules (SiO2 and secondary minerals)

Milky Quartz Pebble

Silicon Dioxide (SiO2)

Limonite

FeO(OH)·nH2O (Hydrated iron oxide-hydroxide)

Prasiolite

Silicon Dioxide (SiO2) with iron impurities

Iron-stained Quartz

Silicon Dioxide with Iron Oxide (SiO2 with Limonite/Hematite impurities)

Chlorastrolite (Isle Royale Greenstone)

Chlorastrolite (Pumpellyite-(Mg,Fe2+): Ca2MgAl2(Si2O7)(SiO4)(OH)2∙H2O)

Pyrite

Iron Sulfide (FeS2)

Chert (specifically a Worked Flint/Knapped Flake)

Chert / Flint (Microcrystalline Quartz, SiO2)

Aquamarine

Beryl (Be3Al2Si6O18 with Fe2+ impurities)

Native Gold (in Jewelry)

Gold (Au)

Rhodochrosite

Manganese carbonate (MnCO3)

Druzy Quartz

Crystalline Silicon Dioxide (SiO2)

Blue Chalcedony

Cryptocrystalline Quartz (SiO2)

Milky Quartz (Vein Quartz)

Silicon Dioxide (SiO2)

Banded Gneiss

Banded Gneiss (High-grade Metamorphic Rock)

Dalmatian Stone

Dalmatian Jasper (a trade name for an igneous microcrystalline rock composed mostly of feldspar, quartz, and dravite)

Fluorite

Calcium fluoride (CaF2)

Clear Quartz

Quartz (Silicon Dioxide, SiO2)

Dalmatian Stone

Dalmatian Stone (a variety of aplite)

Milky Quartz with Iron Staining

Quartz (Silicon Dioxide, SiO2)

Green Quartz (Prasiolite/Adventurine)

Silicon Dioxide (SiO2) with inclusions

Citrine Quartz

Silicon Dioxide (SiO2) with iron impurities

Limonite (Iron Ore)

Limonite (FeO(OH)·nH2O)

Banded Gneiss

Gneiss (Metamorphic rock predominantly containing quartz, feldspar, and mica)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

White Quartz Crystal Cluster

Silicon Dioxide (SiO2)

Polished Hematite Tower

Hematite (Fe2O3)

Ferruginous Quartz

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Quartz Vein with Iron Staining

Silicon Dioxide (SiO2) with limonite/hematite staining

Jasper and Mudstone Composite

Silicified Sedimentary Rock / Jasperoid Pebble

Dalmatian Stone

Peralkaline Quartz-Feldspar Porphyry with Arfvedsonite

Amygdaloidal Basalt

Amygdaloidal Basalt (Mafic Volcanic Rock)

Specular Hematite with Quartz and Limonite

Hematite (Fe2O3) with Quartz (SiO2) and Limonite (FeO(OH)·nH2O)

Vesicular Basalt

Vesicular Basalt (rich in silicate minerals mostly Plagioclase and Pyroxene)

Chert (specifically a stream-worn Chert Nodule)

Sedimentary Cryptocrystalline Quartz (SiO2)

Gneiss (Banded Gneiss)

Gneiss

Greenstone

Metabasalt / Greenschist