Amorphous Solid

Black Onyx

Silicon Dioxide (SiO2) with cryptocrystalline structure

Petrified Wood

Silicified wood (Quartz/Chalcedony replacement of cellulose)

Gold and Cubic Zirconia (San Judas Tadeo Pendant)

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

Agate Geode

Cryptocrystalline Quartz (SiO2)

Quartz Geode

Crystalline Silver Oxide (SiO2) in Calcareous Host

Stichtite in Serpentinite (Atlantisite)

Mg6Cr2CO16(OH)16·4H2O in Mg3Si2O5(OH)4

Quartz Geode

Silicon Dioxide (SiO₂)

Pallasite Meteorite (likely Imilac or Brenham)

Stony-Iron Meteorite (Pallasite)

Banded Agate (Onyx Variety)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Glauconite (Green Sandstone)

Glauconite (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2

Pink Quartz (Inclusion-rich Quartzite)

SiO2 (Silicon Dioxide) with Iron Oxide / Hematite inclusions

Microcrystalline Limestone Pebble

Carbonate sedimentary rock (Calcium Carbonate, CaCO3)

Petrified Wood

Fossilized plant material (Silicon dioxide - SiO2)

Petrified Wood (Silicified Fossil)

Silicified Wood (SiO2)

Bismuth

Bismuth (Bi)

Labradorite

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

Petrified Wood

Fossilized wood / Silicified wood

Druzy Quartz Geode (Partially Open)

Silicon Dioxide (SiO2) within Sedimentary Host Rock

Vesicular Basalt / Scoria (with Iron Oxide Alteration)

Vesicular Basalt

Red Quartzite / Ferruginous Quartzite

Quartzite (primarily SiO2 with Fe2O3 inclusions)

Petrified Wood

Silicified Wood (primarily SiO2)

Wonderstone (Liesegang Sandstone)

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

Quartz Geode

Silicon Dioxide (SiO2) in a Secondary Formation

Sandstone (Quartzose)

Arenite (SiO2 based typically)

Petrified Wood

Silicified wood (primarily Silicon Dioxide, SiO2)

Agate (Common Chalcedony)

Silicon Dioxide (SiO2)

Quartz Geode (Nodule)

Silicon Dioxide (SiO2)

Black Onyx

Silicon dioxide (SiO2) - Chalcedony variety

Basalt (River-worn Specimen)

Extrusive Mafic Igneous Rock

Petrified Wood

Silicified Wood (SiO2)

Yellow Jasper

Silicon Dioxide with Iron inclusions (SiO2)

Agate Geode

Chalcedony (SiO2 - Silicon Dioxide)

Quartz Geode

Silicon Dioxide (SiO2)

Agate Geode

Cryptocrystalline Quartz (SiO2)

Lapis Lazuli (in Matrix)

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

Larimar

Pectolite, NaCa2Si3O8(OH)

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

Native Gold (Au) and Native Silver (Ag)

Black Onyx

Silicon Dioxide (SiO2)

Blue Dyed Agate Geode

Chalcedony (cryptocrystalline Quartz), SiO2

Petrified Wood

Silicified wood (Quartz/Chalcedony replacement of organic matter)

Petrified Wood

Silicified wood (primarily Silicon Dioxide - SiO2)

Petrified Wood

Silicified Wood (primarily SiO2)