Sedimentary (With Some Aspects Of Mineral Replacement)

Mookaite Jasper

Siliceous (chert) sedimentary rock, a form of Jasper

Tiger's Eye

Pseudomorph of quartz after crocidolite (SiO2 with iron inclusions)

Septarian Nodule (Yellow Jasper variety)

Septarian Nodule (comprising Calcite, Aragonite, and Limestone/Bentonite)

Chert (Common Opal/Chalcedony)

Microcrystalline Quartz (SiO2)

Banded Gneiss

Gneiss (quartz-feldspar-biotite metamorphic rock)

River Cobble (Gneiss/Migmatite)

Gneissic Metamorphic Rock (composed mainly of Quartz, Feldspar, and Biotite)

Mixed Gemstone Bracelet

Mixed natural minerals and rocks (e.g., Rhodonite, Malachite, Sodalite, Rose Quartz, Black Tourmaline, Quartz/Chalcedony variants)

Celestite (Celestine)

Strontium Sulfate (SrSO4)

Conglomerate

Conglomerate (Sedimentary Clastic Rock)

Gneiss (specifically a Banded Gneiss pebble)

Gneiss (High-grade Regional Metamorphic Rock)

Lapis Lazuli (Tumbled)

Lazurite-dominated contact metamorphic rock

Trilobite Pygidium (Tail Segment)

Phylum Arthropoda, Class Trilobita (likely order Phacopida)

Gneiss

Gneiss (High-grade Metamorphic Rock)

Sandstone with Liesegang Rings

Arenite with Iron Oxide Liesegang Banding

Red Jasper (Quartzite conglomerate)

Silicon dioxide (SiO2) with Iron inclusions

Jasper with Epidote Vein

Silicon Dioxide (SiO2) with Calcium Aluminum Iron Silicate (Ca2(Al,Fe)3(SiO4)3(OH))

Tiger's Eye (Unpolished)

Pseudomorph of Quartz after Crocidolite (SiO2)

Conglomerate

Conglomerate (clastic sedimentary rock)

Amber

Succinite (Organic Mineraloid)

Clay (as a rock-forming material)

Clay minerals (e.g., Kaolinite group, Smectite group, Illite group, Chlorite group)

Rose Quartz

Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese

Kambaba Jasper

Stromatolite Jasper (Microcrystalline Quartz with Cyanobacteria fossile)

Quartz Geode (likely within Limestone or Dolomite matrix)

Quartz (SiO₂)

Gneiss (specifically a Granitic Gneiss)

Gneiss (Composition: Quartz, Feldspar, Mica)

Chert (variously known as Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Ferruginous Sandstone (with possible trace fossils)

Arenite with Iron-Oxide Cement (SiO2 with Fe2O3)

Banded Iron Formation (BIF)

Banded Iron Formation (Fe2O3 + SiO2)

Blue Sphalerite (likely dyed or treated Druzy Quartz/Agate)

Zinc Sulfide (ZnS) or Silicon Dioxide (SiO2) with trade-name enhancement

Chert (variations include Flint or Jasper)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Biotite (Mica)

Biotite (K(Mg,Fe)3AlSi3O10(OH,F)2)

Conglomerate

Conglomerate (clastic sedimentary rock)

Banded Gneiss

Gneiss (High-grade regional metamorphic rock)

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2)

Petoskey Stone

Hexagonaria percarinata (Fossilized Rugose Coral)

Petrified Wood

Silicified Wood (SiO2)

Mica Schist

Mica Schist (KAl2(AlSi3O10)(OH)2 / K(Mg,Fe)3AlSi3O10(OH)2)

Jasper (specifically Bloodstone or Heliotrope variety)

Silicon Dioxide (SiO2) with iron oxide inclusions

Red Jasper or Chert

Jasper (SiO2, a variety of chalcedony with iron oxide impurities), Chert (SiO2)

Sandstone (specifically Cross-bedded Sandstone)

Arenite (composed primarily of SiO2)

Muscovite Mica

Muscovite (Potassium Mica) KAl2(AlSi3O10)(OH)2

Grooved Maun Ball (Maul/Hammerstone-like Concretion)

Calcareous/Ferruginous Concretion in Sandstone Matrix