Sedimentary Or Metamorphic (Low Grade)

Siltstone

Siltstone (primarily composed of microcrystalline Quartz and Feldspar)

Ironstone Concretion / Goethite-Hematite Geode

Goethite / Hematite Concretion (Fe3O4 / FeO(OH) / Fe2O3)

Ironstone Concretion

Ironstone (Siderite/Goethite/Hematite matrix)

Ironstone Concretion

Siderite or Limonite Concretion (FeCO3 or FeO(OH)·nH2O)

Ironstone (Limonitic Concretion)

Limonite (FeO(OH)·nH2O) with Goethite and Hematite inclusions

Coal

Bituminous or Anthracite Coal

Nephrite Jade

Nephrite (a variety of the Calcium magnesium iron silicate mineral series Actinolite), Ca2(Mg, Fe)5Si8O22(OH)2

Jadeite Jade

NaAlSi2O6 (Sodium Aluminum Silicate)

Anthracite Coal

Anthracite (Carbon-rich metamorphic coal)

Greenstone / Basalt

Metabasalt (often containing Chlorite, Epidote, and Actinolite)

Red Jasper (Chert)

Silicon dioxide (SiO2) with iron oxide inclusions

Tumbled dark stones, likely basalt and slate

Basalt (fine-grained mafic rock) and slate (foliated metamorphic rock); exact identification is uncertain from the image

Polished red tiger’s-eye (likely)

Quartz pseudomorph after crocidolite; chiefly SiO₂ with iron oxides

Tiger’s eye

Quartz (SiO₂) with fibrous crocidolite pseudomorphs and iron oxides

Leopard jasper (orbicular jasper)

Silicified volcanic rock, chiefly microcrystalline quartz/chalcedony (SiO₂) with feldspar and iron-oxide inclusions

Greenstone / Greenstone Pebble

Greenschist (metamorphosed basalt or gabbro)

Bornite

Copper Iron Sulfide (Cu5FeS4)

Red Siltstone

Siltstone (primarily quartz and feldspar sized 0.0039 to 0.0625 mm)

White quartz fragment (likely milky quartz)

Quartz, silicon dioxide (SiO₂)

Carnelian

Silicon Dioxide (Chalcedony variety), SiO2

Quartz vein in greenstone/altered mafic rock

Quartz (SiO₂) with chlorite–epidote-rich metabasalt or greenstone

Polished tiger’s-eye

Tiger’s-eye quartz (fibrous chalcedony/quartz, SiO₂)

Weathered gray metamorphic rock, likely phyllite or slate

Micaceous quartz–phyllosilicate rock; commonly quartz + muscovite/illite ± chlorite

Dark gray slate or phyllite cobble

Slate–phyllite, composed mainly of fine-grained mica, quartz, and chlorite

Tumbled greenstone (likely serpentine or chlorite-rich metamorphic rock)

Serpentinite, approximately Mg₃Si₂O₅(OH)₄, or chlorite-rich greenstone

Aquamarine

Beryllium aluminum silicate (Be3Al2Si6O18)

Polished black stone, likely shungite

Shungite; carbon-rich mineraloid composed mainly of amorphous carbon, with silica and other minerals

Glauconitic Sandstone

Glauconitic Quartz Arenite

Serpentinite

Serpentinite (composed primarily of Serpentine group minerals usually (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4)

Limonite (Limonitic Sandstone)

Hydrated Iron(III) Oxide-Hydroxide ($FeO(OH)·nH_2O$)

Limonite (Iron Ore)

Hydrated iron(III) oxide-hydroxide (FeO(OH)·nH2O)

Red Jasper Pebble

Microcrystalline Quartz (Chalcedony), SiO2

Ferruginous Sandstone (Ironstone)

Sedimentary rock with Limonite/Goethite cement

Jasper

SiO2

Jadeite Jade

NaAlSi2O6 (Sodium Aluminum Silicate)

Chert (with Epidote/Quartz veining)

Cryptocrystalline silica (SiO2) with Epidote/Quartz inclusions

Banded limestone or marble

Calcite-rich carbonate rock; likely veined limestone, possibly low-grade marble (CaCO₃)

Limonite (Ironstone Concretion)

Hydrated iron(III) oxide-hydroxide (FeO(OH)·nH2O)

Polished dark greenstone with quartz vein

Likely chlorite-rich metabasalt or greenschist with a quartz–feldspar vein

Slate

Slate; fine-grained metamorphosed shale, commonly mica- and chlorite-rich

Slate

Slate; primarily fine-grained mica, chlorite, quartz, and clay minerals

Greenstone with Magnetite Veins

Metabasalt (Greenstone)