Man Made Silicate (Anthropogenic Glass)

Feldspar (Orthoclase / Alkali Feldspar)

KAlSi3O8 (Potassium Feldspar / Orthoclase)

Red Quartzite

Quartzite (Metamorphic quartz sandstone)

Beach Pebble (Chalcedony / Chert)

Silicon Dioxide (SiO2)

Sandstone

Sedimentary Rock (Quartz arenite)

Pearls (likely freshwater cultured pearls)

Pearl: nacre, primarily aragonite (CaCO₃) with conchiolin

Banded Jasper

Silicate Mineral (Microcrystalline Quartz / SiO2)

Diamond

Carbon (C)

Sandstone (likely Quartzose)

Clastic sedimentary rock (SiO2 primary)

Common Opal / Chert

Hydrated silica (SiO2·nH2O) or Microcrystalline Quartz (SiO2)

Lepidolite and Rubellite (Pink Tourmaline) in Quartz

K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2 (Lepidolite) and Na(Li,Al)3Al6(BO3)3Si6O18(OH)4 (Elbaite/Pink Tourmaline)

Chert (Black Chert or Flint)

Silicon Dioxide (SiO2)

Sandstone

Arenite (primarily SiO2)

Goldstone

Not a natural mineral or rock. It is an ornamental glass.

Quartzite

Metamorphic Quartzite (SiO2)

Sandstone (specifically Arkose or Quartz Arenite)

Arenite (primarily SiO2 with possible Feldspar)

Mica (Muscovite)

Potassium aluminum silicate - KAl2(AlSi3O10)(OH)2

Chert (variations include Flint/Novaculite)

Chert (formula: SiO2)

Sandstone (with Iron Oxide staining)

Arenite (primarily SiO2 with Fe2O3 staining)

Quartz Pebble with Chlorite or Epidote Inclusions

Silicon Dioxide (SiO2) with inclusions

Chert / Flint

Microcrystalline Quartz (SiO2)

Snowflake Obsidian

Vitreous Volcanic Rock (Amorphous Silicate), SiO2

Weathered tan mineral/rock fragment

Indeterminate from image; possibly iron-stained quartz, feldspar-rich rock, or limonite-bearing material

Quartzite

Quartzite (SiO2)

Chert (Flint)

Cryptocrystalline Quartz (SiO2)

Chert (often called Flint)

Chert (SiO2)

Flint / Chert

Microcrystalline quartz (SiO2)

Chert (specifically Zebra Chert/Flint)

Silicon Dioxide (SiO2)

Chert Concretion (Flint)

Silicon Dioxide (SiO2)

Chert (Quartz Variety)

Chert (Silicon Dioxide, SiO2)

Dendritic Jasper (Bumblebee like Agate)

Silicon Dioxide with inclusions (SiO2)

Smoky Quartz

Silicon Dioxide (SiO2)

Chert (Flint)

Chert (SiO2)

Tumbled amber-colored chalcedony or jasper

Microcrystalline quartz (SiO₂), likely iron-stained chalcedony/jasper

Red Jasper

Silicon Dioxide (SiO2) with Hematite (Fe2O3) inclusions

Chert

Microcrystalline quartz (SiO2)

Sandstone (Quartzose Sandstone)

Arenite (primarily SiO2)

Chert (Flint / Jasper variant)

Microcrystalline Quartz (SiO2)

Quartz (Smoky Quartz variant)

Silicon Dioxide (SiO2)

Chert (Black Flint)

Silicon Dioxide (SiO2)

Chert (Flint)

Silicon Dioxide (SiO2)

Granite

Phaneritic Felsic Igneous Rock

Sandstone

Arenite (SiO2 principal)