Organic Gem Material (Botanical)

Weathered quartz-rich pegmatite, likely feldspar/quartz

Granitic pegmatite; chiefly microcline or plagioclase feldspar (KAlSi₃O₈–NaAlSi₃O₈) with quartz (SiO₂), possibly mica

White quartz-rich rock, possibly milky quartz

Quartz (SiO₂), possibly quartzite or calcite-bearing material

Chert (and Fossilized Brachiopod shell)

Sedimentary Cryptocrystalline Quartz (SiO2)

Quartz-rich metamorphic rock, likely quartzite or quartz vein in schist

Quartz (SiO₂) with probable mica, feldspar, and iron-oxide staining

Red glassy cabochon, likely synthetic ruby or red glass

Uncertain; possible synthetic corundum (Al₂O₃, chromium-colored) or man-made glass

Weathered granite pebble

Granite, chiefly quartz (SiO₂), feldspar, and mica/amphibole

Tumbled blue-green stone, possibly aquamarine or chalcedony

Indeterminate from image; possibilities include beryl (Be₃Al₂Si₆O₁₈) or cryptocrystalline quartz (SiO₂)

Blue chalcedony or blue quartz bead bracelet

Microcrystalline quartz, SiO₂ (chalcedony); possibly treated blue quartz

Opal gemstone pendant

Opal (hydrated amorphous silica, SiO₂·nH₂O)

Tumbled amethyst

Quartz, purple variety; silicon dioxide (SiO₂), colored mainly by iron-related defects

Yellow chalcedony or citrine-like polished stone

Chalcedony (microcrystalline SiO₂), possibly iron-stained quartz

Tumbled quartz pebble (likely milky quartz or chalcedony)

Quartz, SiO₂; possibly microcrystalline quartz (chalcedony)

Vesuvianite (Idocrase)

Vesuvianite, Ca10(Mg,Fe)2Al4(SiO4)5(Si2O7)2(OH)4

Milky quartz

Quartz, silicon dioxide (SiO₂)

Petrified Wood

Silicified Wood (primarily Quartz / Chalcedony: SiO2)

Fossiliferous Limestone / Petrifaction

Sedimentary rock with fossil inclusions / Calcium Carbonate (CaCO3)

Weathered iron-rich rock, possibly meteorite

Uncertain; likely goethite/hematite-rich material, with meteorite possibility

Polished serpentine (likely bowenite/antigorite)

Serpentine-group minerals, chiefly antigorite or lizardite: Mg₃Si₂O₅(OH)₄

Uncut diamond (likely gemstone)

Diamond — crystalline carbon, C

Sedimentary Rock with Crafts (Pet Rock)

Sedimentary rock decorated with synthetic materials

Milky quartz in weathered host rock

Quartz, silicon dioxide (SiO₂), likely occurring in altered igneous or metamorphic matrix

Iron-stained quartz-rich rock (likely quartzite or quartz vein material)

Quartz (SiO₂), commonly with limonite/goethite iron oxides; possible quartzite matrix

Milky quartz in dark host rock

Quartz (SiO₂), likely as a vein or vein fragment; host rock uncertain

Multicolored beryl gemstone bracelet

Beryl, Be₃Al₂Si₆O₁₈; likely mixed aquamarine, morganite, heliodor, and green beryl beads

Chert (likely flint), possibly chalcedony-rich

Microcrystalline quartz, SiO₂ (quartz/chalcedony)

Moldavite

Tektite

Travertine

Travertine (a terrestrial form of Limestone, CaCO3)

Likely iron-stained quartz pebble

Quartz (SiO₂), possibly coated with iron oxides such as goethite or hematite

Likely rough garnet

Garnet group, possibly almandine (Fe₃Al₂(SiO₄)₃); identification is uncertain from the image

Likely garnet, possibly almandine

Garnet group; likely almandine, Fe₃Al₂(SiO₄)₃

Unknown small pale rock fragment

Unidentified light-colored granular mineral aggregate; likely quartz-rich material or limestone

Tumbled green stone, likely serpentine

Serpentine-group minerals, chiefly antigorite and/or lizardite; approximate formula Mg₃Si₂O₅(OH)₄

Likely raw serpentine or green calcite specimen

Tentatively serpentine-group mineral, commonly antigorite or lizardite; alternatively pale green calcite

Quartz-rich rock, possibly granite or pegmatite fragment

Likely quartz–feldspar aggregate; exact identification is uncertain from the photograph

Tumbled pink tourmaline (probable)

Elbaite tourmaline, Na(Li,Al)3Al6(BO3)3Si6O18(OH)4

Sapphire (Rough)

Corundum (Al2O3)

Greenstone, likely serpentinite

Serpentinite; predominantly serpentine-group minerals (Mg₃Si₂O₅(OH)₄), possibly with chlorite, talc, magnetite, or antigorite

Basalt

Basalt

Orthoclase Feldspar

Potassium aluminum silicate (KAlSi3O8)

Rose Quartz

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

Ruby (Raw/Rough)

Corundum (Al2O3 with Chromium trace)

Basalt

Basalt (Aphanitic Mafic Volcanic Rock)