Mineral, Specifically An Iron Ore

Limonite (Ironstone)

Hydrated Iron Oxide (FeO(OH)·nH2O)

Iron-stained Quartz

Silicon Dioxide with Iron Oxide (SiO2 + Fe2O3/FeO(OH))

Chrysocolla-bearing copper ore

Chrysocolla (hydrated copper aluminum silicate, approximately (Cu,Al)₂H₂Si₂O₅(OH)₄·nH₂O), likely mixed with malachite, quartz, and limonite

Basalt with Quartz Veins

Mafic Igneous Rock with Quartz (SiO2) intrusions

Peacock Ore

Bornite (Cu5FeS4)

Hematite Nodule

Hematite (Fe2O3)

Amethyst (Ametrine or Bicolor Quartz variant)

Silicon Dioxide (SiO2) with iron impurities

Red Jasper

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Rounded iron-rich stone, likely hematite-bearing sandstone or ironstone

Hematite/goethite-bearing ferruginous sandstone or ironstone; composition cannot be confirmed from appearance alone

Limonite with Quartz (Gossan)

Hydrated iron(III) oxide-hydroxide mixture (FeO(OH)·nH2O) with Silicon Dioxide (SiO2)

Banded iron formation (ironstone)

Banded iron formation, chiefly hematite/magnetite with chert (SiO₂)

Chalcopyrite

Copper Iron Sulfide (CuFeS2)

Ferruginous Sandstone (Gozzan)

Iron-rich clastic sedimentary rock with Limonite/Goethite

Limonite and Hematite Gossan

Hydrated Iron Oxide Mix (FeO(OH)·nH2O) / Ferric oxide (Fe2O3)

Likely ironstone or iron-rich sandstone fragment

Iron-oxide-cemented sandstone; exact mineral composition cannot be confirmed from the photograph

Agate (Carnelian / Chalcedony)

Silicon Dioxide (SiO2)

Mixed collection of minerals and rocks (Jasper, Carnelian, Granite, and Quartz)

Silicon Dioxide (SiO2) with varying impurities for silicates and igneous aggregates

Hematite

Iron(III) oxide (Fe2O3)

Iron-rich weathered stone, possibly hematite-rich ironstone

Hematite/goethite-bearing ironstone; predominantly Fe₂O₃ and FeO(OH)

Black tumbled stone, likely hematite

Hematite (Fe₂O₃); identification is uncertain from the image alone

Gossan (Limonite/Goethite)

Hydrated iron oxides (primarily FeO(OH)·nH2O)

Possible magnetite fragment

Magnetite (Fe₃O₄), tentative identification

Hematite

Iron(III) oxide (Fe2O3)

Specular Hematite

Specularite (Iron Oxide, Fe2O3)

Botryoidal Hematite (Kidney Ore)

Iron(III) oxide (Fe2O3)

Hematite (Iron Ore Boulder)

Hematite (Fe2O3)

Limonite (Iron Ore)

FeO(OH)·nH2O

Basalt (Tumbled Massage Stone)

Extrusive Igneous Rock

Tumbled dark stone, possibly hematite or black jasper

Uncertain; likely hematite (Fe₂O₃) or fine-grained chalcedony/jasper (SiO₂)

Yellow Jasper

Silicon Dioxide (SiO2) with iron inclusions

Magnetite-rich iron ore (probable magnetite schist)

Magnetite (Fe₃O₄) in a foliated metamorphic matrix, possibly magnetite–biotite schist

Brown Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Weathered iron-rich concretion or laterite fragment

Ferruginous concretion, likely goethite/limonite (hydrated iron oxides) in a clay-rich matrix

Specular Hematite

Hematite (Iron(III) oxide, Fe2O3)

Hematite

Hematite (Iron (III) oxide, Fe2O3)

Hematite

Hematite (Fe2O3)

Mahogany Obsidian

Obsidian (Volcanic Glass with Hematite/Magnetite inclusions), SiO2

Unidentified dark mineral/rock fragment

Indeterminate; appearance may fit a sulfide-bearing rock or iron-rich mineral

Limonitic Iron Ore / Goethite

Hydrated Iron(III) oxide-hydroxide (primarily FeO(OH)·nH2O)

Small weathered rock fragment (likely iron-rich basalt or laterite)

Tentative: basaltic lithic fragment, possibly limonitic/iron-oxide coated

Blue Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2)

Hematite

Iron(III) oxide (Fe2O3)