Igneous And Sedimentary Mixture

Limonite / Goethite (Iron Ore Mineral nodule)

FeO(OH)·nH2O / FeO(OH)

Limonite (Goethite/Ironstone)

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

Basalt (Road Gravel)

Aphanitic mafic volcanic rock (various compositions of plagioclase feldspar and pyroxene)

Limonite (also known as Yellow Ochre or Brown Hematite)

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

Granite (likely biotite granite)

Coarse-grained plutonic rock composed chiefly of quartz, potassium feldspar, plagioclase, and biotite mica

Granite

Granite (Felsic Plutonic Rock)

Granitic rock, likely weathered granite

Granite; primarily quartz, feldspar, and mica

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

Hydrated iron oxides, chiefly limonite (FeO(OH)·nH₂O) and goethite (α-FeO(OH)), possibly cementing sandstone

Ironstone / limonite-rich rock

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

Bumble Bee Jasper

Volcanic Tuff (mixture of SiO2, CaCo3, S, and As2S3)

Weathered iron-rich rock fragment

Provisional identification: limonite/goethite-rich material, likely an ironstone fragment

Limonite

Hydrous ferric oxides (FeO(OH)·nH2O)

Bumblebee Jasper

Carbonate-rich volcanic rock containing Sulfur and Arsenic (Realgar/Orpiment)

Limonite

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

Limonite (Iron Ore)

Limonite (FeO(OH)·nH2O)

Limonite Concretion

Hydrated Iron Oxide-Hydroxide, FeO(OH)·nH2O

Limonite Pseudomorph after Pyrite

Limonite (Hydrous iron oxides, FeO(OH)·nH2O) replacing Pyrite (FeS2)

Weathered iron-rich concretion or limonite/goethite nodule

Limonite (largely hydrated iron oxides; commonly goethite, FeO(OH), and hematite, Fe₂O₃)

Granite Pebble

Granite (Felsic Plutonic Rock)

Smoky quartz crystal cluster

Quartz, silicon dioxide (SiO₂), likely smoky variety with possible feldspar or matrix inclusions

Agate

Silicon dioxide (Chalcedony), SiO2

Weathered iron-rich concretion

Goethite–hematite limonite concretion, likely with quartz and clay minerals

Yellow Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Agate

Silicon Dioxide (Chalcedony), SiO2

Diorite

Diorite (intermediate intrusive igneous rock)

White Agate / Chalcedony

Silicon Dioxide (SiO2)

Granite / Pegmatite Pebble

Felsic intrusive igneous rock

Tumbled sandstone pebble

Quartz-rich sandstone (primarily SiO₂)

Weathered granitic rock fragment

Granitoid, likely granodiorite or granite

Weathered iron-rich rock, likely limonite-bearing sandstone or laterite

Limonite/goethite-rich ferruginous rock; composition commonly FeO(OH)·nH₂O with quartz and clay minerals

Iron-rich banded rock, likely goethite/limonite-rich ironstone

Goethite (α-FeO(OH)) and/or limonite with iron-oxide-stained silica or clay; exact identification requires testing

Conglomerate (or Breccia / Porphyry)

Clastic Sedimentary Rock (Conglomerate / Sandstone)

Limonite (with Goethite/Ironstone)

FeO(OH)·nH2O (Hydrated Iron Oxide)

Weathered iron-rich sedimentary rock (probable laterite/ironstone)

Limonite/goethite-rich ferruginous material; commonly approximated as FeO(OH)·nH₂O with clay and quartz

Iron-rich concretion or weathered ironstone

Goethite–hematite limonite aggregate; commonly described as limonite or ironstone

Weathered iron-rich rock, possibly limonite-bearing sandstone or laterite

Limonite/goethite-rich ferruginous rock; exact identification requires testing

Iron-rich laterite or weathered ironstone

Ferricrete/limonite-rich ironstone; primarily goethite (FeO(OH)) and hematite (Fe₂O₃), with clay minerals

Limonite (often after Hematite or Goethite)

Limonite (FeO(OH)·nH2O)

Biotite-bearing granite or granitic gneiss

Quartz–feldspar granite with biotite and accessory mica/amphibole

Limonite (Iron Stone/Iron Ore)

FeO(OH)·nH2O (Hydrous ferric oxide)

Chalcedony (Agate)

Silicon Dioxide (SiO2)

Iron-rich concretion or weathered ironstone

Limonite/goethite-rich ironstone; commonly hydrated iron oxides such as FeO(OH)·nH₂O