Meteorite (Extraterrestrial Material)

Basalt pebble

Fine-grained mafic volcanic rock, typically plagioclase + clinopyroxene ± olivine and magnetite

Weathered iron-rich sandstone or ferruginous conglomerate

Quartz-rich sandstone cemented by iron oxides/hydroxides (primarily hematite and goethite)

Rounded iron-rich cobble (likely lateritic sandstone or ironstone)

Ferruginous sandstone/ironstone; chiefly quartz (SiO₂) with iron oxides, especially hematite (Fe₂O₃) and goethite (FeO(OH))

Small dark mineral/rock fragment

Indeterminate; possibly biotite-rich schist, graphite, or metallic sulfide

Likely iron-rich rock or meteorite fragment

Indeterminate; possible hematite-/magnetite-bearing material

Vesicular iron-rich slag or weathered metallic ore

Indeterminate; likely Fe-oxide-bearing slag (magnetite/hematite) rather than a specific natural mineral

Iron meteorite (probable)

Fe–Ni metal, commonly kamacite and taenite

Slag (Industrial Glass/Metal)

Ferrous slag or Glassy silicate byproduct

Slag (Industrial)

N/A (Anthropogenic Slag)

Tektite (Indochinite)

Tektite (High-silica amorphous glass)

Tektite

Tektite (high-silica natural glass)

Slag (Industrial Byproduct)

Artificial silicate/iron byproduct

Porphyritic basalt (likely olivine- or pyroxene-bearing basalt)

Basalt; fine-grained mafic volcanic rock, commonly containing clinopyroxene and/or olivine phenocrysts

Basalt

Fine-grained mafic volcanic rock, chiefly plagioclase feldspar and pyroxene, commonly with olivine

Ironstone concretion (probable hematite–goethite-rich ironstone)

Iron oxide/hydroxide concretion; chiefly hematite (Fe₂O₃) and goethite (FeO(OH)), with possible magnetite and quartz

Ferruginous Slag (Iron Smelting Byproduct)

Anthropogenic Vitreous Silicate (often containing Fayalite: Fe2SiO4)

Iron-rich concretion or weathered ironstone

Goethite–hematite-bearing ferruginous concretion; exact identification requires testing

Slag (Industrial Byproduct)

Anthropogenic Vitreous Silicate material

Likely polished basalt or iron-rich metamorphic rock

Basaltic rock, chiefly plagioclase and pyroxene; exact identification requires testing

Possible iron-rich basalt or industrial slag

Basalt, likely Fe–Mg silicate rock; exact identification is uncertain from the blurred image

Ferruginous Sandstone (Ironstone Conglomerate fragments)

Ferruginous clastic sedimentary rock (SiO2 cemented by Fe2O3)

Iron-rich hematite/goethite rock (ironstone)

Hematite (Fe₂O₃) with goethite/limonite (FeO(OH)·nH₂O), likely in a weathered ironstone matrix

Iron-rich hematite/goethite concretion (likely limonite)

Hematite (Fe₂O₃) with goethite (FeO(OH)) and limonite

Chondrite Meteorite

Stone Meteorite (Chondrite)

Likely metallic mineral specimens

Probably native iron or iron oxide/hydroxide material; exact identification requires testing

Unidentified dark pebble

Undetermined; possibly polished basalt, chert, or iron-rich stone

Weathered iron-rich rock, possibly limonite-bearing basalt or ironstone

Indeterminate; likely basaltic or ferruginous rock containing iron oxides/hydroxides such as hematite (Fe₂O₃) and limonite/goethite

Polished vesicular basalt (likely scoriaceous basalt)

Basalt, aphanitic mafic volcanic rock; chiefly plagioclase, pyroxene, and iron-rich oxides

Unidentified weathered rock fragments

Likely mixed silicate rocks; specific identification requires testing

Dark metallic-looking mineral specimen, possibly magnetite

Magnetite (Fe₃O₄), tentative identification

Likely silicon carbide (carborundum)

Synthetic silicon carbide (SiC), likely blue-green crystalline grit

Fossiliferous limestone (likely ammonite/gastropod-bearing)

Bioclastic limestone; predominantly calcite (CaCO₃)

Industrial slag (iron/copper smelting slag)

Multiphase vitreous metallurgical slag; commonly iron-silicate glass with metal-oxide and metallic inclusions

Weathered iron-rich rock fragment

Likely limonite/goethite with hematite and iron-bearing silicates; exact identification requires testing

Likely iron-rich volcanic rock (basalt/pyroclastic fragment)

Basaltic rock, potentially weathered andesite; exact identification requires testing

Small dark tumbled stone (likely basalt or iron-rich mineral)

Uncertain; possibly basalt (fine-grained plagioclase–pyroxene rock) or magnetite-rich material (Fe₃O₄)

Weathered iron-rich concretion or ironstone cobble

Goethite–hematite–limonite-rich ironstone; exact identification requires testing

Vesicular Basalt (Iron Scoria)

Aphanitic Mafic Igneous Rock with Vesicular Texture

Olivine in Basalt

Peridotite / Forsterite ((Mg,Fe)2SiO4)

Chondrite Meteorite

Ordinary Chondrite (OC)

Possibly polished basalt or gabbro

Basalt/gabbro; chiefly plagioclase feldspar and pyroxene, with possible olivine or magnetite

Chondrite Meteorite

Undifferentiated Chondrite