Ironstone Concretion (Limonite/Goethite)
Ferruginous Sandstone or Limonite (FeO(OH)·nH2O)
sedimentary
Category
Metamorphic (Low Grade)
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Epithermal Gold Ore (in Quartz/Rhyolite matrix)
Auriferous Quartz (Au + SiO2)
mineral
Prehnite
Prehnite, Ca2Al2Si3O10(OH)2
Mineral
Emerald
Beryl (Be₃Al₂Si₆O₁₈), specifically the green variety colored by trace amounts of chromium or vanadium.
Mineral
Corundum
Corundum (Al2O3)
Mineral
Greenstone (Amygdaloidal Basalt)
Amygdaloidal Basalt (frequently composed of Plagioclase Feldspar, Pyroxene, and Olivine with Chlorite inclusions)
igneous
Jade
There are two distinct minerals commonly known as Jade: Jadeite (NaAlSi2O6) and Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2). Based on the appearance, these spheres are likely Nephrite.
Mineral
Anthracite Coal
Anthracite (Metamorphosed Coal)
sedimentary
Diabase (Greenstone)
Diabase (also known as Dolerite)
igneous
Red Scoria (Lava Rock)
Scoria (highly vesicular basaltic/andesitic rock)
igneous
Venetian Gold Granite
Phaneritic Felsic Igneous Rock (Granite)
igneous
Jadeite (Nephrite)
Ca2(Mg,Fe)5Si8O22(OH)2
metamorphic
Jadeite (Jade)
NaAlSi2O6 (Sodium Aluminum Silicate)
metamorphic
Pyrite
Iron Sulfide (FeS2)
mineral
Limonite (Iron Ore)
Hydrated iron(III) oxide-hydroxide (FeO(OH)·nH2O)
sedimentary
Gossan (Iron Hat)
Limonitic Gossan (Fe2O3·nH2O)
sedimentary
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
mineral
Caliche (with Lichen Cover)
Calcium carbonate-cemented soil layer (CaCO3)
sedimentary
Ferruginous Sandstone
Arenite with Iron Oxide cement (primarily Fe2O3)
sedimentary
Conglomerate
Conglomerate (Sedimentary rock)
sedimentary
Limonite (Ironstone Concretion)
Hydrated iron(III) oxide-hydroxide (FeO(OH)·nH2O)
mineral
Ironstone Concretion
Ferruginous Sandstone / Iron-rich Sedimentary Rock
sedimentary
Turquoise
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
mineral
Ferruginous Sandstone
Sandstone with iron oxide (Hematite/Limonite) cement
sedimentary
Ironstone Concretion / Goethite Nodules
Ironstone (composed primarily of Goethite FeO(OH) and Limonite)
sedimentary
Milky Quartz
Silicon Dioxide (SiO2)
Mineral
Pearl (Imitation or Cultured)
Calcium Carbonate (Aragonite/Calcite) - CaCO3
Mineraloid (Organic)
Anthracite Coal
Anthracite (Carbon ≥ 86%)
sedimentary
Ferruginous Sandstone (Gritstone)
Clastic sedimentary rock with iron-rich cement (FeO(OH)·nH2O)
sedimentary
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
mineral
Milky Quartz with Iron Staining
Quartz (Silicon Dioxide, SiO2)
mineral
Limonite Concretion (Ironstone)
Limonite (FeO(OH)·nH2O) with Goethite and Hematite
sedimentary
Ferruginous Sandstone (Ironstone)
Sedimentary rock with high iron oxide content (Fe2O3 / FeO(OH))
sedimentary
Limonite (Oxidized Iron Ore)
FeO(OH)·nH2O (Hydrous ferric oxide)
mineral
Ironstone Concretion
Limonitic/Hematitic Concretion
sedimentary
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Conglomerate
Conglomerate (clastic sedimentary rock)
sedimentary
Ironstone Concretion (Pot Stone)
Siderite or Limonite Concretion (FeCO3 or FeO(OH)·nH2O)
sedimentary