Mineraloid (Human Made Geological Specimen)

Quartz Geode (partially formed)

Silicon Dioxide (SiO2)

Quartz Geode

Silicon Dioxide (SiO2)

Ambergris

Physeter macrocephalus excreta (Ambergris)

Gold Ore

Auriferous Quartz and Sulfide Mineralization in Host Rock

Bauxite

Bauxite (Al(OH)3, γ-AlO(OH), and α-AlO(OH))

Obsidian

Obsidian (volcanic glass, amorphous silica rich rock)

Chert (Jasper/Flint variant)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Clear Quartz

Silicon Dioxide (SiO2)

Amygdaloidal Basalt with Epidote

Vesicular Basalt with secondary Epidote/Quartz mineral infill

Biotite Schist

Biotite Schist (Rich in K(Mg,Fe)3AlSi3O10(OH)2)

Limonite (with goethite)

Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)

Banded Calcite (often commercially called 'Mexican Onyx')

Calcium Carbonate (CaCO3)

Moqui Marble (Ironstone Concretion)

Iron Oxide Concretion (Fe2O3 / FeO(OH))

Garnet Schist

Almandine Garnet in Mica Schist (Fe3Al2(SiO4)3)

Biotite Schist with Garnet

Garnet-Biotite Schist

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Jade (Nephrite)

Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)

Chert (Jasper/Chalcedony variety)

Microcrystalline Quartz (SiO2)

Fossiliferous Limestone with Rugose Coral

Calcium Carbonate (CaCO3) featuring Rugosa (extinct order of solitary and colony corals)

Limonite (Iron Stone Concretion)

Limonite (Hydrous Iron Oxide) - FeO(OH)·nH2O

Chert (Flint Nodules)

Microcrystalline Quartz (SiO2)

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chlorite Phantom Quartz

Silicon Dioxide (SiO2) with Chlorite group inclusions [(Mg,Fe)3(Si,Al)4O10(OH)2·(Mg,Fe)3(OH)6]

Sandstone (with Liesegang rings or joints)

Clastic Sedimentary Rock (primarily Quartz with Iron Oxide cement)

Quartz Vein in Sedimentary Matrix

Silicon Dioxide (SiO2) with host rock

Mahogany Obsidian

Obsidian (volcanic glass with hematite/magnetite inclusions)

Chert / Flint

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Granodiorite Core

Granodiorite

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Diabase (Greenstone)

Diabase (also known as Dolerite)

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Chert (Jasper variation)

Chert (Silicate mineral, SiO2)

Sedimentary rock with quartz veining

Laminated siltstone or mudstone with hydrothermal quartz veins

Banded Onyx (Calcite Marble)

Calcite (CaCO3) - Trap-rock or Cave Onyx

Chert (Flint)

Silicon Dioxide (SiO2)

Chert (Jasper/Agate variety)

Microcrystalline Quartz (SiO2)

Stichtite in Serpentine (Atlantasite)

Mg6Cr2CO3(OH)16·4H2O in Mg3Si2O5(OH)4

Chert (often referred to as Flint or Jasper when pigmented)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Oak-grain Laminate (Industrial/Decorative Furniture Finish)

Melamine Resin-impregnated Decorative Paper on Particleboard (Cellulose/Thermosetting Plastic)

Chert Nodule (Commonly known as Flint or River Rock)

Silicon Dioxide (SiO2)

Quartz (Iron-Stained)

Silicon Dioxide (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)