Sedimentary (Secondary Classification For A Weathered Mineral Specimen)

Quartz (Milky Quartz Pebbles)

Silicon Dioxide (SiO2)

Jasper (Iron-rich)

Silicon Dioxide (SiO2) with Fe2O3 (Hematite) inclusions

Cardstock (Paper)

Cellulose (C6H10O5)n

Chert (Nodule)

Silicon Dioxide (SiO2)

Basalt with Quartz Veins

Basalt (composition: SiO2, MgO, FeO, Al2O3, CaO)

Sandstone (likely Quartzose Sandstone with mineral staining)

Arenite (composed mainly of SiO2)

Flesh-toned Siltstone

Siltstone (composed of microscopic Quartz and Feldspar grains)

Banded Gneiss

Gneiss (typically quartz, feldspar, mica, amphibole composition)

Chert (Jasper/Opaline variety)

Silicon Dioxide (SiO2)

Basalt (Vesicular)

Vesicular Basalt

Yellow Aventurine

Silicon Dioxide (SiO2) with inclusions

Chert (often called Flint in dark varieties)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Limestone

Calcium Carbonate (CaCO3)

Granite

Phaneritic Felsic Igneous Rock (Granite)

Quartz (possibly milky quartz)

Quartz (Silica; SiO₂)

Carnelian and White Quartz Bracelet

Silicon Dioxide (SiO2) - specifically Carnelian (Chalcedony) and Rock Crystal/Snow Quartz

Leopard Skin Jasper

Jasper (Silicon Dioxide with impurities), SiO2

Olivine in Basalt matrix

Peridotite (Mg, Fe)2SiO4

Milky Quartz with Iron Staining

Silicon Dioxide (SiO2)

Ferruginous Conglomerate (or Iron-Rich Concrete/Slag)

Clastic Sedimentary (Silicon Dioxide/Iron Oxide matrix)

Red Jasper (Polished)

Jasper (Iron-rich Microcrystalline Quartz, SiO2)

Chert (with Liesegang Banding)

Microcrystalline quartz (SiO2)

Graphite-veined Quartzite

Meta-sedimentary Quartzite with Carbonaceous/Graphitic Inclusions (SiO2 + C)

Gold Nugget / Flake

Native Gold (Au)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Yellow Banded Agate

Silicon Dioxide (SiO₂)

Chert (variously Flint or Jasper gravel)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Sandstone (with Iron Staining)

Clastic sedimentary rock (primarily SiO2)

Basalt with vesicles/amygdules

Basalt (containing volcanic glass and plagioclase)

Milky Quartz (Water-Worn Pebble)

Silicon Dioxide (SiO2)

Yellow Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Chert

Chert (microcrystalline quartz)

Bull Quartz (Milky Quartz)

Quartz (Silicon Dioxide - SiO2)

Banded Chert (or Banded Jasper)

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

Fossilized Shark Tooth

Fossil Chondrichthyes (various genera such as Carcharias or Odontaspis)

Gneiss (specifically a Banded Gneiss pebble)

Gneiss (High-grade Regional Metamorphic Rock)

Banded Gneiss

Gneiss (pronounced 'nice')

Chert (variously identified as Flint)

Microcrystalline Quartz (SiO2)

Petrified Wood

Silicified Wood (primarily SiO2 - Silicon Dioxide)

Carnelian Agate

Silicon Dioxide (SiO2)

Lepidolite

Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)

Sandstone with Bedding Planes

Arenite (Sedimentary rock composed primarily of sand-sized minerals)