Mineral, Specifically An Iron Ore

Limonite/goethite-rich ironstone

Limonite (hydrated iron oxides, chiefly FeO(OH)·nH₂O), commonly mixed with goethite and hematite

Likely weathered iron-rich rock fragment

Probably limonite/goethite-bearing material; exact identification requires testing

Hematite

Hematite (Fe2O3)

Hematite or Goethite-rich Ironstone

Ironstone (Oxidized Iron Ore)

Hematoid Quartz

Ferruginous Quartz (SiO2 with Fe2O3 inclusions)

Limonite

FeO(OH)•nH2O

Polished hematite

Hematite (Fe₂O₃), likely a tumbled specimen

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

Hematite

Iron(III) oxide (Fe2O3)

Botryoidal hematite-goethite iron-oxide specimen

Hematite (Fe₂O₃) with goethite (FeO(OH)), likely coating quartz or iron-rich matrix

Specular Hematite with Quartz and Limonite

Hematite (Fe2O3) with Quartz (SiO2) and Limonite (FeO(OH)·nH2O)

Ferruginous Quartz

Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions

Earthy Hematite / Goethite Surface

Iron Oxide (Fe2O3 – α-FeO(OH))

Limonite Nodule

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

Limonite (Ironstone Concretion)

Limonite (FeO(OH)·nH2O)

Botryoidal limonite/goethite nodule

Limonite (largely goethite, FeO(OH), with hydrated iron oxides)

Agate Nodules

Cryptocrystalline Quartz (SiO2)

Mahogany Obsidian

Volcanic Glass with Hematite inclusions

Banded iron formation (specimen, possibly hematite–jasper)

Banded iron formation; chiefly hematite (Fe₂O₃), magnetite (Fe₃O₄), and silica (chert/quartz), with possible limonite/goethite staining

Tumbled hematite (likely hematite-rich ironstone)

Hematite, Fe₂O₃; possibly mixed with magnetite or goethite

Polished hematite sphere

Hematite (Fe₂O₃), likely a polished specular or massive variety

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Limonite (Iron Ore)

Limonite (Hydrated iron oxide - FeO(OH)·nH2O)

Weathered iron-rich rock, possibly hematite-bearing breccia

Hematite (Fe₂O₃)-rich lithic fragment; exact host rock is uncertain from the image

Ironstone / Weathered Hematite

Iron oxide-rich sedimentary rock with Goethite/Hematite

Tumbled or cut iron-rich mineral specimen

Likely limonite/goethite (hydrated iron oxides), possibly weathered hematite

Polished hematite-rich ironstone

Hematite (Fe₂O₃), likely mixed with magnetite and iron-rich jasper

Yellow Jasper

Tectosilicates (SiO2) with Goethite/Iron oxide inclusions

Red Jasper

Silicon Dioxide with Iron Oxide inclusions (SiO2 + Fe2O3)

Tumbled magnetite-rich rock

Magnetite (Fe₃O₄), likely in a mafic-rock matrix

Weathered iron-rich rock, possibly hematite-bearing chert

Hematite (Fe₂O₃), likely mixed with silica and iron oxides

Banded iron formation fragment (likely jasper-rich ironstone)

Banded iron formation (BIF), commonly hematite/goethite with chert or jasper; Fe₂O₃/FeO(OH) and SiO₂

Weathered iron-rich rock, likely limonite/goethite-bearing laterite

Limonite–goethite aggregate, commonly approximated as hydrated iron oxides (FeO(OH)·nH₂O)

Gossan

Iron-rich regolith (mainly Limonite and Goethite, FeO(OH)·nH2O)

Gossan (Iron Hat)

Limonitic Gossan (Fe-oxide/hydroxide complex)

Lemon Quartz (Orizaba/Citrinated Quartz)

Silicon Dioxide (SiO2) with iron impurities/treatment

Weathered iron-rich rock, possibly basalt or ironstone

Indeterminate; likely Fe-oxide-bearing basaltic rock (commonly magnetite/hematite in a silicate matrix)

Likely specular hematite

Hematite (Fe₂O₃), probably a micaceous/specular variety

Iron-rich vesicular rock, possibly weathered scoria or ironstone

Likely oxidized basaltic scoria (Fe-oxide-bearing volcanic rock); exact identification requires testing

Chalcopyrite in Gossan

Chalcopyrite (CuFeS2) in a Limonite-rich Gossan matrix

Botryoidal hematite (ironstone)

Hematite, Fe₂O₃

Limonite (Ironstone)

Limonite (FeO(OH)·nH2O)