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Magnetite

Magnetite (Fe3O4)

Iron (Hematite variety)

Iron (Fe) / Hematite (Fe2O3)

Amazonite

Potassium Aluminum Silicate (KAlSi3O8)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Amethyst

Amethyst (Silicon Dioxide, SiO2)

Banded Agate

Silicon Dioxide (SiO2)

Sandstone (Graywacke type)

Clastic Sedimentary Rock (Lithic Sandstone)

Quartzite

Quartzite

Pyrite

Iron Disulfide (FeS2)

Vesicular Basalt (Scoria)

Extrusive Mafic Volcanic Rock (FeO-SiO2-MgO)

Aquamarine with Sunstone

Aquamarine (Be3Al2Si6O18), Sunstone (Na,Ca)Al(Si,Al)Si2O8

Hematite

Iron(III) oxide (Fe2O3)

Quartz Pebble

Silicon Dioxide (SiO2)

Fuchsite (Green Muscovite in Quartz)

K(Al,Cr)2(AlSi3O10)(OH)2 - Chromium-rich Muscovite

Chert (Flint Nodules)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Greywacke (River Slikkenstone)

Greywacke (Impure Sandstone)

Smoky Quartz

SiO2 (Silicon Dioxide)

Diorite (River Pebble)

Diorite (Intermediate intrusive igneous rock)

Chert (specifically a nodule with Chalcendony/Agate banding)

Microcrystalline Quartz (SiO2)

Banded Chert (or Banded Jasper)

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

Jasper

Jasper (Silicon Dioxide, SiO2)

Smoky Quartz with Feldspar

Quartz (SiO2) with Potassium Feldspar (KAlSi3O8)

Quartz (Iron-Stained)

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Quartz Geode

Silicon Dioxide (SiO2)

Smoky Quartz

Smoky Quartz (SiO2)

Amethyst (Rough Quartz)

Silicon Dioxide (SiO2 with Iron impurities)

Chert (Agatized Chert)

Microcrystalline Quartz (SiO2)

Yellow Chert (Microcrystalline Quartz)

Chert / SiO2 (Silicon Dioxide)

Quartz (Iron-Stained)

Silicon Dioxide (SiO2)

Diorite

Diorite (Intermediate intrusive igneous rock)

Petrified Wood

Silicified Wood (SiO2)

Native Gold in Quartz

Native Gold (Au)

Quartz (White/Milky with Iron Staining)

Silicon Dioxide (SiO2)

Green Chalcedony (likely Chrysoprase or Green Onyx)

Silicon Dioxide (SiO2) with trace nickel or chromium inclusions

Smoky Quartz (Rough Specimen)

Silicon Dioxide (SiO2)

Schist

Mica Schist (primarily composed of quartz, feldspar, and mica)

Clear Quartz (Rock Crystal)

Quartz (Silicon Dioxide - SiO2)

Petrified Wood

Silicified Wood (primarily SiO2)

Muscovite Mica

Muscovite (KAl2(AlSi3O10)(OH)2)

Quartz (Druzy/Macro-crystalline)

Silicon Dioxide (SiO2)

Pyrite

Iron Sulfide (FeS2)