Anthropogenic (Man Made Material Processed By Nature)

Tumbled milky quartz

Quartz (SiO₂), microcrystalline or massive variety

Weathered green-gray stone, likely serpentinite or chlorite-rich metamorphic rock

Probable serpentinite (antigorite–lizardite), possibly chlorite schist or altered basalt

Milky Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Milky Quartz with Chlorite / Mica inclusions

Silicon Dioxide (SiO2) with phyllosilicate inclusions

Quartz Sand (Beach Sand)

Silicon Dioxide (SiO2)

Granite

Phaneritic Felsic Igneous Rock

Likely milky quartz with iron-oxide inclusions

Quartz, silicon dioxide (SiO₂)

Sandstone (Ferruginous)

Ferruginous Sandstone (SiO2 with iron oxide cement)

Heat-Treated Amethyst (Commercial Citrine)

Silicon Dioxide (SiO2) - Macro-crystalline Quartz

Red Sandstone

Arenite (primarily Quartz with Hematite cement)

Tumbled carnelian agate with dark mineral inclusions

Carnelian, an orange variety of microcrystalline quartz (chalcedony), SiO₂; dark inclusions are likely iron oxides/hydroxides, possibly hematite, goethite, or a basaltic/matrix fragment

Granodiorite

Granodiorite

Granite

Intrusive Phaneritic Felsic Igneous Rock

Emerald (Rough)

Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)

Iron-stained quartz-rich rock, possibly goethite-bearing quartz

Quartz (SiO₂) with iron oxides/hydroxides, likely goethite or limonite

Sandstone

Arenicola (comprising mostly Quartz, SiO2)

Dark flint or chert fragment

Microcrystalline quartz (SiO₂), likely flint/chert

Chrysotile Asbestos

Chrysotile [Mg3Si2O5(OH)4]

Tumbled Hematite with Quartz/Chert (Specular Hematite)

Fe2O3 (Iron Oxide)

Blue Quartzite (Aventurine variety)

Silicon Dioxide (SiO2) with inclusions of Dumortierite or Magnesio-riebeckite

Granite

Granite (composed primarily of Quartz, Feldspar, and Mica)

Chert (also known as Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Calligraphy Stone

Mariam Jasper (Fossiliferous Limestone composed of Hematite and Shell remains)

Weathered granite or granitic gneiss

Granite: quartz, feldspar, and mica; possibly weakly foliated gneiss

Tumbled quartz-rich pebble

Microcrystalline quartz (SiO₂), possibly weathered chert or chalcedony

Flint or chert

Microcrystalline quartz (SiO₂), commonly with chalcedony

Iron-rich laterite or limonite/goethite-bearing rock

Hydrated iron oxides, chiefly goethite (α-FeO(OH)) and limonite (FeO(OH)·nH₂O), likely in a lateritic matrix

Agate (or Chalcedony)

SiO2 (Silicon Dioxide) - a cryptocrystalline variety of quartz

Sandstone (Quartz Sandstone)

Clastic sedimentary rock (primarily SiO2)

Tumbled blue-green stone, likely chrysocolla or dyed chalcedony

Probable chrysocolla (hydrated copper aluminosilicate; variable composition), though appearance could also represent dyed chalcedony

Granite

Phaneritic Felsic Igneous Rock

Tumbled green aventurine (probable)

Quartzite dominated by quartz (SiO₂), with green mica/fuchsite or chlorite inclusions

Limestone

Calcium Carbonate (CaCO3)

Sandstone (likely Fossiliferous)

Arenite / Sedimentum arenaceum

Green aventurine cabochon (likely)

Quartzite/aventurine quartz, predominantly SiO₂ with possible fuchsite mica

Conglomerate (Asphaltic/Anthropogenic)

Clastic sedimentary rock / Bituminous mixture

White quartz pebble

Quartz (SiO₂), likely milky quartz

Tumbled quartz (likely clear quartz)

Quartz, silicon dioxide (SiO₂)

Banded Gneiss (with possible weathered sulfide or iron staining)

Gneiss, potentially with iron oxide/hydroxide staining (e.g., limonite) or weathered sulfides

Tumbled serpentine

Serpentinite; chiefly antigorite, lizardite, and/or chrysotile [Mg₃Si₂O₅(OH)₄]

Weathered, iron-stained rhyolite pebble (possibly rhyolitic volcanic breccia)

Rhyolite, a felsic volcanic rock; mainly quartz and alkali feldspar with minor plagioclase, altered mafic minerals, and iron-oxide staining

Pink Granite

Phaneritic intrusive felsic igneous rock