Amorphous Solid

Agate Geode / Nodular Chalcedony

Silicon Dioxide (SiO2) with impurities

Porphyritic Basalt (or Porphyry)

Porphyritic Basalt (Mafic volcanic rock with phenocrysts)

Banded Agate (Onyx Variety)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Bronzite

MgSiO3 (Enstatite with 10-30% FeSiO3 in solid solution)

Black Onyx (Tumbled)

Silicon Dioxide (SiO2)

Microcrystalline Limestone Pebble

Carbonate sedimentary rock (Calcium Carbonate, CaCO3)

Labradorite

Labradorite (a variety of Plagioclase Feldspar), Na(AlSi3O8) to Ca(Al2Si2O8)

Petrified Wood (Silicified Fossil)

Silicified Wood (SiO2)

White Agate (Chalcedony)

Agate (Silicon Dioxide - SiO2)

Agate Geode

Silicon Dioxide (SiO2) - Chalcedony / Quartz Variety

Dyed Crackle Quartz

Silicon Dioxide (SiO2) with synthetic dye

Geode (Quartz)

Silicon Dioxide (SiO2)

Quartzite

Quartzite (SiO2)

Quartzite (specifically an iron-stained or Carnelian-colored variety)

Silicon Dioxide (SiO2) with iron oxide inclusions

Geode (Unopened)

Siliceous Concretion / Geode

Basalt (River-worn Specimen)

Extrusive Mafic Igneous Rock

Quartz Geode (Nodule)

Silicon Dioxide (SiO2)

Agate (Common Chalcedony)

Silicon Dioxide (SiO2)

Black Onyx

Silicon dioxide (SiO2) - Chalcedony variety

Petrified Wood

Silicified wood (primarily Silicon Dioxide, SiO2)

Ocean Jasper (Orbicular Jasper)

Silicon Dioxide (SiO2) with iron and other impurities

Quartzite Pebble (River Rock)

Metamorphic Quartzite (predominantly SiO2)

Black Onyx

Silicon Dioxide (SiO2)

Banded Gneiss

Gneiss (quartz-feldspar-biotite metamorphic rock)

Yellow Jasper

Silicon Dioxide with Iron inclusions (SiO2)

Gold and Cubic Zirconia (San Judas Tadeo Pendant)

Native Gold (Au) with Synthetic Cubic Zirconia (ZrO2)

Quartz Geode

Silicon Dioxide (SiO₂)

Pallasite Meteorite (likely Imilac or Brenham)

Stony-Iron Meteorite (Pallasite)

Pink Quartzite

Quartzite (primarily SiO2)

Yellow Chalcedony (Carnelian/Yellow Agate)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Quartz Geode

Silicon Dioxide (SiO2)

Red Quartzite / Ferruginous Quartzite

Quartzite (primarily SiO2 with Fe2O3 inclusions)

Blue Dyed Agate Geode

Chalcedony (cryptocrystalline Quartz), SiO2

Gold and Silver (Metal Components of an Antique Pocket Watch)

Native Gold (Au) and Native Silver (Ag)

Pink Quartz (Inclusion-rich Quartzite)

SiO2 (Silicon Dioxide) with Iron Oxide / Hematite inclusions

Petrified Wood

Silicified Wood (SiO2)

Wonderstone (Liesegang Sandstone)

Silicified Sandstone with Liesegang Rings (SiO2 + FeO(OH))

Quartz Geode

Silicon Dioxide (SiO2) in a Secondary Formation

Agate Geode

Chalcedony (SiO2 - Silicon Dioxide)

Gold (in Opaque Matrix/Jewelry)

Native Gold (Au)

Agate Geode

Cryptocrystalline Quartz (SiO2)

Lapis Lazuli (in Matrix)

Na8[Al6Si6O24]S2 (Lazurite as the primary component)