Mineral, Specifically An Iron Ore

Weathered iron-rich river pebble

Ferruginous sandstone or ironstone; composition likely quartz with iron oxides (hematite/goethite)

Weathered jasper-rich ironstone

Brecciated jasper/chert with iron oxides and hydroxides (SiO₂ with hematite, goethite, and limonite)

Jasper

Silicon Dioxide (SiO2) with iron oxide impurities

Iron-rich Gossan with Quartz

Limonite and Goethite with Silicon Dioxide (SiO2)

Sandstone (Ferruginous)

Arenite (with iron oxide cement, Fe2O3)

Limonite (Iron Ore)

Limonite (FeO(OH)·nH2O)

Yellow Quartz (Citrine or Iron-Stained Quartz)

Silicon Dioxide (SiO2)

Rose Quartz

Silicon dioxide / Quartz (SiO2)

Chert (Iron-stained)

Chert (Microcrystalline Quartz, SiO2)

Orange Calcite

Calcium Carbonate (CaCO3)

Orange Calcite

Calcium Carbonate (CaCO3)

Orange Calcite

Calcium Carbonate (CaCO3)

Limonite (Iron Ore)

Limonite (FeO(OH)·nH2O)

Ironstone concretion

Iron-oxide-cemented sediment, commonly goethite (FeO(OH)) and hematite (Fe₂O₃)

Weathered iron-rich rock (likely ironstone or altered basalt)

Probable limonite/goethite-bearing basalt or ironstone; exact identification requires testing

Yellow Ochre / Limonite

Limonite (inter-mixed iron oxides and hydroxides, primarily FeO(OH)·nH2O)

Gossan (with Limonite and Hematite)

Goethite (FeO(OH)), Limonite (FeO(OH)·nH2O), and Hematite (Fe2O3)

Limonite (Yellow Ochre)

Hydrated Iron Oxide (FeO(OH)·nH2O)

Dendritic Agate

Silicon Dioxide (SiO2) with Manganese/Iron inclusions

Hematite (Botryoidal / Kidney Ore)

Iron Oxide (Fe2O3)

Specular Hematite

Hematite (Fe2O3)

Rose Quartz

Quartz (SiO₂), specifically a variety of Quartz

Limonite

FeO(OH)·nH2O (Hydrated iron oxide)

Iron-rich weathered rock, possibly limonite-bearing sandstone or laterite

Goethite–hematite/limonite assemblage, likely in a ferruginous sandstone or weathered host rock

Ferruginous Quartz

Silicon Dioxide (SiO2) with Hematite/Limonite (Fe2O3·nH2O) inclusions

Botryoidal Hematite (Kidney Ore)

Iron(III) oxide (Fe2O3)

Limonite with Opal infusion

FeO(OH)·nH2O (Limonite) / SiO2·nH2O (Opal)

Iron-rich weathered rock, likely limonite/goethite-bearing laterite

Limonite (variable hydrated iron oxides; chiefly goethite, α-FeO(OH))

Iron-rich weathered rock (probable limonite/goethite)

Limonite, a mixture dominated by goethite (FeO(OH)) and related hydrated iron oxides

Limonite/Goethite Iron Concretion

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

Red Jasper

Microcrystalline Quartz (SiO2) with iron oxide inclusions

Limonite / Goethite pseudomorph

Hydrated Iron Oxide (FeO(OH)·nH2O)

Limonite (Ironstone)

Limonite (FeO(OH)·nH2O)

Weathered metallic rock, possibly iron-rich ore

Uncertain; possible goethite–hematite limonite or iron-nickel meteorite

Bornite

Copper Iron Sulfide (Cu5FeS4)

Blue Sapphire (in a faceted jewelry setting)

Corundum (Al2O3) with trace Iron and Titanium

Hematite (Tumbled)

Iron(III) oxide (Fe2O3)

Red Jasper (with Quartz)

Silicon Dioxide (SiO2) with Hematite inclusions

Rose Quartz

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

Iron-rich hematite specimen

Hematite (α-Fe₂O₃), likely with limonite/goethite and host-rock impurities

Botryoidal hematite/goethite specimen

Hematite (Fe₂O₃), likely mixed with goethite (FeO(OH))

Hematite (Iron Ore)

Hematite (Fe2O3)